Determining the Best Air Pump Size for Hydroponics

One of the most daunting things for a new hydroponic gardener is in maintaining their hydroponic reservoir.

With many factors to consider, it can be overwhelming, yet it isn’t as challenging as it first appears. Gardeners may comprehend the influence temperature has, and the amount of nutrients they require. However, they often struggle with the concept of oxygenation levels in their solution.

You may know it is beneficial to use an air pump; however, you may find yourself not fully understanding, how to determine the best air pump size for hydroponics. While an air pump may not appear to do too much, plants need to receive oxygen from the water to survive. An air pump, in many cases, may not be too large, yet it can harm your crops if it is too small.

Why You Need an Air Pump in Hydroponics?

In a hydroponic system, the gardener must deliver everything their plants require.

Many gardeners know about water, light, and the nutrients, yet equally important is oxygen. While there may be some oxygen taken up by the upper portions of the plants, the majority is taken up by the root system.

If you grow in soil, there are pockets of air between the grains of soil, so your plant won’t be sat in just water.

Once you look at Hydroponic systems and you don’t use an air pump, water loses the oxygen and stagnates. Once this happens, your plants quickly drown as a result.

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With the introduction of an air pump, the bubbles add dissolved oxygen into your water. if you could look close enough, you would see these tiny pockets in the same manner as those found in soil

You can also find another couple of benefits of using air pumps. First is to keep your solution mixed, and second is that it can help to reduce the temperature of your solution, particularly if your pump is sucking in cool air.

When you look at some systems, you can get by without using an air pump, yet even these can benefit significantly as plants love all the oxygen they can get. More oxygen means they can take up more nutrients, and they can grow to their full potential.

The Noise of Hydroponic Air Pumps

One drawback of an air pump is that of the noise they produce. While it is the function of your air stones to create the bubbles, the air pumps function is to suck in air from outside the reservoir.

In contrast, a water pump has the noise suppressed by the water. While all air pumps will make a noise, you will find some quieter than others. When checking your pump, you will see the manufacturer places a level on the packaging.

Any pump you purchase should be 45 decibels or lower, and then it will blend with the surrounding noises.

Other Air Pump Considerations

The function of an air pump is simple, yet there are a few other things you need to consider to get the best from it.

Tubing from your pump into your tank should be black as a way of stopping light getting into your reservoir. Most are often supplied with clear, and you may need to change these.

The second thing to consider is the size of your system and the reason for calculating the size of the air pump you require. You can find air pumps that offer one outlet, or others comprise up to eight outlets.

With multiple pipe connections, you have the chance to place air stones in different areas of your reservoir, or you can run multiple systems from one pump.

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Many larger-scale growers may opt for two pumps rather than one to act as a failsafe. If one fails and it can cope with your system, then your plants won’t suffocate.

Lastly, it would be best if you were sure your pump matches your air stones. An air stone that is too large may have air coming just from one location, and thus other areas may block prematurely. In addition to this, any air stones you use ought to produce smaller bubbles.

With this, you find the oxygen dissolves easier as the bubbles travel slower, and more of the water surface is disturbed. Larger bubbles merely rise to the surface faster and will break the water surface less.

Air stones come in multiple sizes, yet once you have a pump that can drive air through all of the stone, you can find a four-inch size is ideal.

You may not hear much about this, and the issue stems from aquariums more than hydroponics, though it could be an issue.

If you have a deep tank rather than shallower horizontal, there can be back pressure and water can seep back through the tube into your pump. You will find this can be another reason to have a larger pump than you may think you require.

Calculating the Size of Air Pump for Hydroponics

You can look at purchasing an air pump in many ways, although there is one rule of thumb that a few gardeners use, it is often seen as leading to overkill for your system.

Buying an air pump that has a wattage equal to your number of gallons in your reservoir can lead you to purchase a pump you don’t need. You will see this happens to be a none technical way of selecting your ideal pump.

While you can follow this method, a lot depends on the size of your tank to the extent of the pump you require. One good thing to know is that it is almost impossible to have too much air in your water. The only time this would be an issue is if the water was being thrown from the top of your reservoir.

It is a pump that is too small that causes issues because it can’t oxygenate your solution enough for all your plants.

A pump you need has to deliver at least 500-600 CC (cubic centimeters) per minute. If you see 500-600 ml per minute, the volume of air is the same, and it is a quick 1 to 1 conversion.

For home gardens, even the cheapest pumps can deliver this, although you need to think about your pump in operation.

It is possible to turn your pump off on occasions for limited periods though it isn’t advisable, and your pump ought to be on 24/7. Commercial grade air pumps often come with a single outlet that can connect to a larger hose, and from this, you can connect multiple branches of smaller hose connectors.

Even though these are more costly, they are not overly expensive and will be more durable than smaller air pump variants.


When it comes down to the purchasing decision, unless you have a larger than average garden, you can find most of the available pumps will deliver a steady stream of air to your system.

How long the cheaper models can do this is questionable, so it can be a better option to move upmarket and purchase one that you know will deliver the reliability you require.

Besides this, if you want to go with the failsafe method and opt for two air pumps, you can easily find two middle of the road size pumps that offer plenty of air throughput without reaching the top end of your budget.

Even if you think the pumps appear to be overpowered, you can quickly reduce the number of air stones, although your plants will appreciate the additional oxygen.

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How to use Rockwool to Kick start your Hydroponic Growing

One of the toughest challenges for any new hydroponic gardener is to determine which is the best growing medium that will meet their needs. With several to choose from, it can be daunting, yet one keeps rising to the top.

Rockwool is a versatile material and has been used for well over 40 years. It is ideal for seedlings and for use in some systems, yet there are still concerns how to get the best from this material.

Here, we will look at everything you need to know about Rockwool, and how you can benefit from its use in your garden.

What is Rockwool?

Many people will have seen Rockwool, or a very close relative of it without realizing. What was once used as insulation for roofing or building projects was found to be an effective growing medium for hydroponics when there was a slight change to its structure.

Rockwool comes under a couple of different names, and one of the common ones being “Stonewool.” This is man-made, and to do this, they take basalt rock, which is an old volcanic rock, and melt it at high temperatures along with limestone.

Once it reaches a molten lava stage, this is spun into fibers much like cotton candy. Once these fibers are made, they add a binder into the mix and compress the resulting material into a mat. From here, it will be cut into a variety of shapes and sizes that meets the needs of hydroponic growers.

Sizes you can often find are slabs, cubes, croutons, granulate blocks and starter plugs. These are found to retain moisture to almost ideal conditions, it will retain oxygen and because of the fine structure, it never impedes the growing of plants rooting systems. Rockwool can actually promote a strong vigorous growth.

What Can I Grow Using Rockwool?

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There are all manner of plants and vegetables, which can be grown in Rockwool. While commercial growers use it for germinating lettuce before they transplant them to NFT systems, home growers can use larger Rockwool blocks for growing all manner of leafy greens, herbs, peppers, tomatoes and cucumbers among others.

Growers who use their system for cut flowers find that both Gerberas and Roses grow well when planted in Rockwool.

Once new growers see the benefits of Rockwool, they begin to look at how they can benefit from using it in their garden. For many, the uses do fall down to either germinating seeds, or when cloning new plants, however, larger blocks are more versatile than just using Rockwool starter plugs for this purpose.

No matter what the use, the properties of Rockwool make it an almost perfect growing medium for plants. In comparison to its size, it can hold a large amount of water. This makes it ideal in systems where there are dry periods, and growers don’t want their growing medium to dry out completely.

This feature also acts as a security measure in case there are power outages, or there is a pump or timer failure.

If water retention wasn’t a good enough reason, then the ability to hold almost 20% oxygen between the fibers is. This delivers lots of oxygen to the root zones and makes it hard to actually over water their plants.

Larger 4-inch cubes are used for the bigger plants we saw above, yet the plugs of around 1.5 inches are often used for germination and cloning.

Rockwool makes it easier for new growers, in what could be a stressful time. Using Rockwool, they can keep their seeds damp enough without them sitting in a waterlogged environment.  When it comes to cloning, part of the old plant will be taken from another and planted so it can grow into a new plant all of its own.

This can be a more successful and cheaper way of growing plants for many growers because it will be an identical clone of the original plant, which was the donor.

For this method to be successful there does need to be lots of humidity around the cutting. If it dries out too much, then a plant will revert to self-preservation mode and stop trying to grow new roots.

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Any method of growing needs to be in a sterile environment, and the way they manufacture Rockwool means it is 100% inert. The heating process it goes through during the manufacturing process means there is little chance of fungi or bacteria entering into Rockwool.

Steps in Using Rockwool for Planting Seeds

It may appear daunting when planting seeds for the first few times; however, it can be very straightforward and successful when using this growing medium.

Here are the steps to follow when planting seeds.

  1. Rockwool preparation – soak your cubes well in pH adjusted water. They should have a pH of 5.5 to 6.5.
  2. In the hole in the top of the plug, insert two seeds. Using a fine object such as a toothpick push the seeds toward the bottom of the hole.
  3. Pinch the top of the hole closed or cover with a small piece of Rockwool.
  4. Add all your starter plugs to a nursery tray and place a humidity done over the top. Keep the temperature around 70-80 degrees Fahrenheit.
  5. Check every couple of days and make sure the cubes are not drying out. Either water sparingly or mist them with a water bottle.
  6. Once you see your seeds sprouting, remove the plugs from under the dome and place them under your growing lights.
  7. Once you see a dominant seedling, trim back the smaller one to prevent growth. Never try to remove this smaller shoot as it can damage the shoots of the larger seedling.   
  8. Once these reach between two or three inches in height, you can transplant them to your system. When doing so, there is no need to try to remove the starter plug; this can go directly into your growing medium of choice.

Steps for Propagation Using Rockwool in Hydroponics

Propagation of plants can be harder for new growers until they understand where they need to cut from the donor plant. However, the steps for using the Rockwool cubes are no harder than doing so when growing from seeds.

  1. Make sure your Rockwool cubes are soaked will in pH-adjusted water.
  2. Make sure to water your donor plant well the night before you begin propagation
  3. Take the main stem of the donor plant and cut 3 to 4 inches of leaf stem from as close as you can to the main stem of the plant. Be careful not to damage the node.
  4. Take the cut end and dip it into some rooting hormone
  5. Take the cutting and place it into your cube, but make sure it doesn’t start to emerge from the bottom.
  6. Take your nursery tray and half fill with vermiculite of perlite.
  7. Place the cubes on top of this growing medium.
  8. Close the moisture dome to lock in the moisture and maintain a temperature of around 80 degrees Fahrenheit.
  9. Once roots begin emerging, open the lid slightly and increase more the day after.
  10. Remove the dome completely a few days later once the first roots appear.
  11. Once roots are showing through the bottom of the cub, transplant to your system.

Preparing Rockwool for Use

When using Rockwool, it is important to prepare it before use. While there are other growing mediums, which are pH-neutral such as coco coir and clay pebbles (Hydroton), Rockwool has a naturally high pH of around eight.

This occurs because of the limestone that is mixed with the basalt during manufacturing. If you don’t make sure you adjust the medium before use, then this high pH will prevent plants being able to uptake these nutrients.

Plants prefer conditions that are more acidic, hence the adjustment of the pH before use.

The steps for doing so are easy, yet they can be a little time consuming, so allow yourself a few days before you need to use your new batch of Rockwool.

The first step is to soak your cubes in water, which is acidic. This will dissolve the lime, which forms during manufacture. Distilled water is the best option because you know what the pH will be. Water from the faucet can vary depending if you are in a soft or hard water area.

You should adjust the water so the pH drops to around 5.5. If it goes below five, then this can begin damaging the fibers. Once you do this, allow them to soak up this pH-adjusted water for 24-hours. If these blocks are for use in your system, then locate them in position and run your system without plants until your system pH stabilizes at around 5.5 to 6.0.

Things to Do, and What Not to Do With Rockwool

Using Rockwool can be straightforward, and this can be seen from the amount of growers, which use it. However, there are a few things you need to do, and some things you should to gain the full benefits of this growing medium.

Here we will look at all the things you do need to do:

Pre-soaking Rockwool

When you purchase this growing medium, it will feel very light, as it will be very dry. It is crucial to first wet it sufficiently before you use it. To know it is ready for use, you should submerge the medium in water that is balanced to a pH of 5.5 until there are no more bubbles emerging from the blocks.

By this submersion, the water can penetrate all the tiny pores and holes that are on the inside of the medium. While some growers soak for extended periods, it can be enough to be from seconds or minutes for the starter plugs, or several minutes for the larger 4-inch blocks. It is better to leave it as long as you can to be sure it is thoroughly soaked.

Once you have made this pre-soak, then you need to let it stand and drain. Water will flow and then stop, the medium will still be damp as the moisture only comes from the larger pores where it lets oxygen inside. This gives you the ideal water to oxygen ratio for your plants.

Before using for your plants, you should be sure to wet them with your nutrient solution. After the initial drain, the remaining nutrients will be directly available for your plants. Soaking with just water will weaken the nutrient concentration inside the blocks.

Never Unwrap Your Cubes

The larger blocks will come wrapped in a kind of plastic foil. This won’t let any light inside, and it is there for a reason. This has the same function as your other growing pots. Not only will it prevent air pruning by keeping the light out, it will keep the roots inside.

One other reason this covering needs to stay on the block is it helps prevent algae on the sides. In the case of slabs, these will be fully covered. Because you can’t fit these into buckets, you can soak them from the top with your nutrient solution, and after they have stood, you can make drainage holes on the underside.

Make Sure You Have Good Drainage

All plants will absorb more water than nutrients. You will have a buildup of these salts in your growing medium over time if you don’t allow for a full run-off. As your root zones are irrigated, this new solution pushes the previous slats closer to the bottom of the growing medium.

If there isn’t enough drainage or run-off to allow these salts to drain away, it will become unhealthy for your plants. You need to allow between 20 and 30% of the solution volume going in, and draining from the bottom as a maximum. This will help retain the ideal conditions in the plants rooting zone.

Reuse or Recycle Your Rockwool

When you are using horticultural Rockwool, you may read or hear myths, which say you can’t reuse it or recycle it safely after use.

You can in fact use the larger blocks again as long as you are sure there are no roots remaining. These will rot, but you can purchase enzymes that will help get rid of these, and after you do this, you can reuse them again for a different type of crop.

Rockwool in essence is a rock and it can be broken up and added to compost or added directly to soil garden beds. The only area you should be using Rockwool a second time is for starting your plants.

Here are a few things you should never do when growing with Rockwool:

Never Squeeze Rockwool

Because this growing medium retains so much fluid, new growers may be under the impression there is too much water in the block. Growers should never squeeze their blocks to remove excess water. Squeezing removes too much water as well as damaging the structure of the blocks.

The structure is already ideal for plant growth, so all it needs is wetting and letting it drain naturally before use.

Never Over Stack Your Pots with Rockwool

If your system irrigates from the bottom, you should be cautious of how tall your pots are. Water will never wick more than five or six inches, no matter how good the medium is at absorbing water. Gravity will prevent it from rising higher than this. If you are using a bottom feeding system, be sure the tops of your pots are no higher than this.

Top feeding systems are not as much of a problem because the solution waters from the top. This will fill all the fibers sufficiently before it comes to the time to drain.

Rockwool Usage Tips

There are a few things growers should understand before they begin using Rockwool for the first time.

Health Concerns When Using Rockwool 

Because there is such a similarity with home insulation and Rockwool, many growers are led to believe it can be dangerous to inhale any dust or particles.

For any growing medium, it is advisable to wear a mask when handling these in their dry state. This can relieve any discomfort, as can wearing rubber gloves in case there is any skin irritation. The initial soaking should wash away any of these particles, and from that moment, the blocks should always be damp so the particles will never rise into the air.

Preventing Algae on Rockwool

Like any growing medium in a hydroponic system. A surface, which is moist and exposed to light, can be the ideal conditions for algae growth. Many growers know this all too well, and even if it doesn’t cause problems, it doesn’t look very nice.

To prevent this, they may cover the tops of their large Rockwool blocks with dark plastic to stop light hitting the damp surface. This can be the same for any area of your system where light gets to where your solution sits. Tanks, tubing and grow troughs being prime examples.


After you have taken the initial steps to prepare your Rockwool for use, you will find that it will not affect the pH of your system like many growers think.

Because there is such a good water holding capacity of Rockwool, it is easy to see why growers begin to think this. It is the accumulation of salts in the growing medium as the plants absorb water. Rockwool is one of the easiest and most effective growing mediums to use.

Growers who are concerned with their system pH can easily adjust this by reducing the amount of nutrients, or when they top off with fresh water. There can be fluctuations between just over five all the way to just over a pH of seven, and plants may never show any ill effects. There is a reason why so many growers use this man-made material, and once every grower understands the simple rules above, they too can experience great plant growth by using this easy to use and inexpensive growing medium.

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Beginners Guide to Vertical Farming at Home

Whilst reading about hydroponics, potential growers may become confused with the term “Vertical Gardening.” This is just another term for indoor gardening, yet it can take on many different forms. What they all have in comparison to each other is they are recognized as being a sustainable way to grow healthy plants and vegetables in the home.

Here we will take a look at all you need to know about this gardening method, and how you can benefit from beginning any of the gardening methods, no matter how large or small your growing space can be.

Vertical Gardening Concepts

This kind of gardening can be carried out in any space you can imagine. Commercial growers are using tall buildings, old warehouses, or even old converted shipping containers. Home growers are finding places that are ever more ingenious where to set up these systems, from basements, sunrooms to spare rooms and attics.

What they all have in common is that the plants they grow are all grown in layers. Every method, which is used, will fall under the same umbrella of controlled environmental agriculture.

Following these concepts, growers will be controlling everything from administration of nutrients, the humidity, temperatures and artificial lighting. While in some cases there is the use of natural sunlight, this isn’t the only means of lighting, and it will be supplemented by artificial means.

One other thing all these growing methods have in common is they will all be based around hydroponics in one way or another. Once we begin looking at growing upward with a central system, which uses far less water, we can begin to see why these methods of growing are beneficial.

The amount of arable land reduces every year, so there does need to be alternative methods of growing crops for the ever-increasing world population.

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Adding to this, there are some quick benefits when using these vertical gardens with hydroponics:

  • Can grow seventy-five times more food per square foot than in soil
  • No need for pesticides or fungicides
  • Food can be healthier and safer to eat
  • Food can be grown all year round
  • Food can be grown in regions where it wasn’t previously possible

What is Controlled Environment Agriculture?

This we saw is an umbrella of technologies that are all geared toward the production of food. CEA has the aim of delivering crops the utmost protection while delivering the optimal growing conditions through the entire growing cycle of the crops.

These enclosed growing areas go much further than just using a hydroponic system to make use of a smaller space. The entire growing methods will be optimized where everything is taken into consideration such as water, space, energy consumption, labor and the capital investment.

While this means of growing can also utilize aquaponics, and aeroponics, for the home grower, these systems may not be as feasible as they are for commercial ventures.

One area which is under continual development is that of “Biofortification” where crops are bred to increase their nutritional value. This can be accomplished by selective breeding from different strains of plants, or through genetic engineering and cloning.

These methods vary from regular fortification as they focus on making the food healthier and more nutritious as the crops are growing instead of adding additional nutrients to the crops while they are being processed.

How Does Indoor Small Scale Indoor Farming Work?

Growers who are thinking of utilizing these methods of growing crops will need to go through several factors, which dictate the way the system will work, and how successful it can be.

Unlike a regular hydroponic system, there are plenty more things to consider. Because many crops will be grown in layers, this means that there is not as much opportunity for taller plants in this system type. When you add into this the types of plants which are ideal, it may be the growers ends up growing too much of the same.

It is for this reason, there does need to be some form of a feasibility study conducted. This will show if what the growers wishes to achieve is cost effective, or they may need to design a growing space which allows them to follow the racking growth system for some crops and a separate area for a more conventional system.

Here are some of the factors, which will determine the viability of vertical farms for the home gardener.

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1# Layout

The goal of indoor farming is to make full use of the available space. It is here where growers need to maximize the growing capacity per square meter or foot. To do this easily, growing upward is the key.

2# Light Sources

Growers can use natural light sources, and supplement these with grow lights; however, this may not always be possible. There may be a need for reflectors, rotating beds or another means of making sure the same amount of light falls on all the plants for the specified time.

3# Growing Methods

It is here where the different system types come into play. These can be hydroponics, aeroponics or aquaponics. This will be dictated by the growing area and the type of system used.

4# Sustainability

Everything needs to be supplied by the grower, and if this isn’t done in the right manner, or the right amounts, then it won’t be possible to sustain the garden. Included in this can be rain catchment tanks, wind turbines or growing spaces that can be used for other things as well. A vertical garden will also need to be running all year round to maximize crop growth and reduce overall running expenses.

Small Scale Vertical Gardening for the Home Grower

For home growers, there are many ways they can make use of the concepts and build systems. These come in some very ingenious forms, with one of the simplest and most effective being the window garden, which was developed by a professor from Belgium. Willem Van Cottenham came up with a simple kitchen garden system that makes use of natural sunlight and recycled plastic bottles.

This method takes a number of bottles and strings them together; these hand from the upper most part of the window frame and have a small window cut into the sides of the bottles where net cups can be placed on a growing medium of choice.

At the top of the window is a small reservoir where nutrients are pumped with a small pump, from here they then make their way out of drip emitters into the top most bottles. This acts like a regular drip system, yet the nutrients pass through the first bottle and into the second, and then the third.

At this point, they return to a second catchment reservoir to be reused and circulated back to the top at set intervals.

The same simple concept can be used with plants being placed outdoors rather than inside windows, yet this is ideal for people who lack space.

This concept will be limited to what it can grow, yet there is another form of vertical gardening, which has taken the world by storm almost as much as the interest in hydroponics. Micro-greens are the first shoots from plants and are often used as a garnish in restaurants.

However, they have been found to contain many more benefits, such as an increase in the nutrition they deliver. The popularity of these is the way they grow, and how quick they can be harvested.

Micro-greens follow the vertical gardening ethos down to the finest of details. They are grown in shallow trays and will be stacked on shelves with a set distance between each. Hanging above will be a grow light that is used once the seeds have germinated. Once these greens are ready to harvest, they can be any height from around one inch to around three inches, yet this will depend on the seeds used.

Crops in Micro-greens can be harvested in between ten and fourteen days. Such is the popularity and the ease of this kind of crop and the growing setup required there are many businesses formed on the back of this concept because it is something, which can begin small and scale up in any area of a home.

Vertical gardening around the home doesn’t need to be difficult. The concepts can even be used to supplement regular growing spaces because of the limited space they use. When it comes to the feasibility, this method will help growers save money on groceries, whilst delivering healthier foods onto the table.

These systems are sustainable and make it easy for anyone who lacks a suitable area for a full sized hydroponic system to do their part in growing their own food and putting less strain on the environment.

What Can Be Grown in Vertical Farming?

Depending on the base structure of your vertical gardening system, it is possible to grow near enough anything. However, just because it is possible to grow almost anything, doesn’t mean it makes sense to do so.

There is a point where some crops are not worth growing, or they are not suitable for a family. One other thing, which needs consideration, is for growers who are seeking a commercial venture, and are looking at crops that they can sell. The chances of selling your crops and the cost of production are the most crucial factors at this stage.

Regardless of whether you are growing to sell, or for personal consumption, you will need a feasibility study to understand you are heading in the right direction.

At the end of the day, making the right choices of crops is the best way to make sure you will make you vertical garden a success.

Here is a breakdown of how to look at the determining factors, and then a look at some of the best crops you can grow in vertical gardening systems.

1# Economics & Viability

There are many crops that make sense to grow, yet from a financial stance, they make little sense to grow. This is true if you plan to sell, because if you can’t make money from one of your crops, there can be a few reasons for this:

  • Limited profit due to no demand
  • Production costs are too high
  • Wrong kind of climate – heating, lighting and cooling costs are too much

This can be the same for the home grower, but to a lesser degree. However, you don’t want to find you are spending more on producing your healthy vegetables, than it would cost to purchase them.

2# Timing of Harvests

This can affect small commercial ventures as much as it can affect a home grower. When you take the time from your seedlings to the time, they can be harvested and marketed “A Turn,” this needs to make sense.

Crops, which grow fast, or have a fast turn such as mint, basil, collard greens lettuce and other similar growing vegetables, will help growers reduce their liability. From the start, a grower will already know they are no more than six weeks from a harvest.

If you are looking to grow crops that have a slow turn, they will have a higher value when selling. A recommendation for a split to balance each other out is a high percentage of greens to herbs.

For a home grower who is after enough for consumption, the same will ring true. It makes no sense to grow more lettuce than you can consume, likewise, you don’t want to grow too many slow turn crops where you will be waiting for a harvest, and you may need to resort to going back to the supermarket.

Here are some of the best crops for you to grow in your vertical farm at home.

Best Vertical Growing Crops


There are several varieties you can choose from, although Tuscan kale is one of the more popular. These will take a larger vertical system as they can grow quite large. Aside from that, they can take care of themselves and don’t need too much attention.


Once you understand how fast your lettuce will grow, and how much you can consume, or sell? You will see there is a consistent demand throughout the year. With dozens of variety available, it will never become tiresome when you can have a fresh crispy salad at the times of year you least expect it.

Collard Greens

If you have the right setup, these are ideal for growing at home because you can pluck these rather than harvest the entire plant. Chard is a smaller variety of collard green and can be easier to control. This cooks similar to spinach, and can be harvested on a number of occasions if you only take around a third of the plant as a maximum. This will grow back and deliver a larger yield.


Many growers find that when they have a vertical garden, Basil shines as it grows better in these methods than many other systems. There is also a steady demand for Basil, so it can be a decent crop to grow for home consumption, or to be the first you grow for a small commercial enterprise. It can be harder to grow, and harvest, yet the benefits of doing so are well worth it.

Woody Herbs

The smaller woody herbs such as Oregano, Thyme and Rosemary can be a little choosy when it comes to growing. Because of their nature, they do prefer a drier footing when growing. They also have a slow turn in comparison to other crops, yet these are so distinct in aroma and flavor, it can be worth dedicating a small portion of a vertical garden to these. Growers can also find there is always a strong demand for these in many different markets.

Mint and Chives 

For beginners, there is nothing easier to grow than mint and chives. These are generally grouped with herbs, yet they have a quick turn. Chives looks like grass and is very easy to harvest as a whole, or you can cut what you require. Mint can take over a system as it has a rapid growth, so it is advisable to not plant too much to begin with.


Vertical gardening may just be a term for indoor gardening, yet there is much more to it than that. With the number of unique designs growing where the most unusual spaces are used. These are pushing vertical gardening to the limits.

Home growers may already have a system in mind, or in place, yet taking a step back and having a rethink can dramatically increase the yields they can expect from their garden as a unit. Something as simple as Micro-greens don’t require too much to set up in terms of cost, or in care, yet what they deliver far outweighs the little space they take up.

Vertical gardening is seen as the way forward to solve the world’s problems for an increasing population, and the reduction in farming land.

It is never too late for any grower to begin using the concepts from above to increase their yields without increasing their impact on the environment.

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How to Transfer Plants from Hydroponics to Soil

Many growers who have hydroponic gardens are happy with the plants and crops they grow, and that is sufficient for their needs. There are however others who use hydroponics as a means of growing plants and then transferring them to soil.

This can be for several reasons, yet no matter what the reason for doing so, there are some steps and things growers need to do to ensure their plants make the transition without receiving a shock to their system and suffering as a result.

The same can be done in reverse where plants are moved from soil to a hydroponic system, however, for a method it can be easier to accomplish, as there is no soil to contend with on your plants.

Why Would I Transplant into Soil?

One of the primary reasons for doing this is to use hydroponics as a means of having a healthy start to an outdoor garden. When outdoor growing seasons begin, there is the choice of growing from seeds, or from seedlings.

Seeds take time and there can be some failure rates encountered, commercially bought seedlings can be expensive and on certain occasions, they can be hard to find.

Any grower, who has an outdoor garden, can take advantage of growing their own seedlings in a fraction of the time so they can make the most of their outdoor garden and the growing season with fewer failures.

These indoor systems can also help alleviate any issues that crop up with the unexpected forces of nature, which can interrupt what should be a successful start to a growing season. Not only that, but using hydroponics to start off your seedlings means you are ready to go as soon as you harvest outside after some slight soil preparation.

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It doesn’t matter if you are transplanting out of choice, or because it is essential you do so, there are some things to be wary of. From what can easily be a daunting task can become straightforward for any different hydroponic scenario that you face.

Transplanting Hydroponic Clones and Cuttings

While seeds are an option for gardeners, there is more of a swing toward using cuttings and seedlings, hence the increase in the need for transplanting from a hydroponic system back into soil.

The two most common areas of hydroponics that take place before these transplants are the domed incubation grow trays where small rockwool starter plugs are used, or the more complicated mist propagation systems.

The great news for gardeners is that both of these systems are perfect for outdoor gardeners to use, and are compatible with their soil systems once the seedlings or cuttings have begun to show a good healthy rooting structure.

One primary reason this is a good option apart from getting a kick-start, and missing the chances of bad weather is that growers can over time find an ideal mix of environmental factors, genetics and mix of nutrients. For this reason, many experienced growers preserve the donor plants. Here they can carry on the genetics of the plants and thus they are ensured a level of consistency for good harvests.

One other factor that growers have no need to grow from seeds which could deliver either male or female plants. This is another level of consistency as they will be aware of what they have when they begin growing their seedlings or cuttings.

Steps for Transplanting into Soil

Here are the easy to follow steps for transplanting into soil from your hydroponic system.

  • Take a suitably sized pot, the larger the plant, the bigger the pot you will require. These should be roughly four to six inches wide. Plants being transplanted into soil will need more space for their roots. Give them around four to six inches of space to allow them to grow.
  • Fill it with a growing medium that adds some buffer for your plants until they are ready to be fully transplanted into gardens. Many growers opt for soilless peat mixtures, which have a better pH than planting directly into soil.
  • Make a hole in the center of the pot, which is larger than the plants rooting system, and the starter plug if used. If you have plants, which are growing together, you will need to separate the roots carefully as this can cause plant shock easily.
  • Sprinkle the hole with mycorrhiza. This beneficial fungus helps as a growth enhancer. This helps plants absorb nutrients from soil as it helps to increase the area of absorption.
  • Place the plant in the hole and then cover with additional dirt
  • Once you have planted, you do need to water immediately. Hydroponic plants are accustomed to being watered regularly to help minimize plant shock levels they will experience. You can use a quarter strength nutrient solution in the beginning until they start finding their own nutrients from the earth.
  • After about a week, you can cut back on watering until you only have to water as the top inch of soil is dry.

One you have done this your plants will need to be in areas with plenty of light, yet they may not be directly accustomed to the outside temperatures. There will be a period of hardening off they need to go through for a week before they can last in outdoor temperatures.

Soil Transplanting Tips

If your plant is large, it can help to trim back some of the foliage. This pruning will help the plants, as they don’t need to search for nutrients for more leaves and can start to grow steadily.

Most gardeners who use rockwool cubes or plugs intend to transplant into soil. A gardener that uses the larger cubes around the six-inch size won’t be looking to move plants into an outdoor garden or soil filled pots.

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Net pots will be entwined with a plants rooting system if plants are more than a few weeks old. If these do need to be planted in soil, it can be a case of planting the entire net pot as well as the plant. Trying to remove the intricate rooting system can kill the plant.

Plant Shock When Moving into Soil

If you have done everything right, your plants will take hold and begin growing as they should. However, if they are suffering from shock, there are some signs you will notice. This can happen quickly, or it can happen over the first couple of weeks after moving into soil.

Leaves can turn yellow to brown and may wither up and darken. These can fall from the plant with a light touch. At this stage, leaves and stems begin to wilt and dry.

There are some things you can do to try and cure plant shock, yet these may not work in every case.

  • Trimming back the plant by at least one-third can help plants focus on their roots.
  • Keep rooting systems moist is vital. Because there is a difference in the watering, there will be more onus on good drainage through the soil. It can be easy for plants to find themselves in standing water.
  • Add a water and sugar solution. While this isn’t 100% proven, it can help and even if it doesn’t work, it won’t harm your plants.


Moving plants from a hydroponic system is a feasible option for many gardeners. By taking this route, even if it can be a little hard for new growers can be worth the effort. Growers can have seedlings or growing cuttings that offers up more plants to move outside.

Rather than using seeds and having to wait, plants will be instantly growing. This offers the chance to plant more crops throughout the year they may have previously not been able to.

If things don’t work out as intended, there is still the option for growers to carry on growing in their system. It can be a win-win situation, and there will be less overall wasted effort in the outdoor side of a garden.

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How to Make Liquid Fertilizer for Hydroponics

Hydroponics is a great way to grow plants at home. New growers can quickly recover initial build costs, and their power bills are not as bad as they initially anticipated. One cost they may wish was cheaper, or there were alternatives is the price of liquid fertilizer.

Because these mainly comprise of water, shipping can be more expensive, and they don’t last very long once they are in use. This repeat purchasing can make a big hole in anyone’s budget.

However, it is possible to make your liquid fertilizer, so you save some money! You do need to be sure you include all the required nutrients that are in the store-bought alternatives so plants can thrive without deficiencies.

How do you make liquid fertilizer for your hydroponic system? The quickest way is to follow these simple steps:

  1. Place one gallon of organic compost or a pound of worms castings into a large bucket with a lid
  2. Stir in water and agitate the contents well
  3. Aerate the mixture with an aquarium air pump
  4. Set the bucket aside for three days. Stir every day

The strained liquid is your fertilizer and is ready to put into your hydroponics system. You can use animal or plant byproducts to make a liquid fertilizer as well.

Here we will show you all you need to know about making liquid fertilizer that is suitable for use in a hydroponic system.

Why is it Possible to Make Liquid Fertilizer?

The nutrient mixes and the boosters and deficiency formulas are straightforward to make. New growers may wonder why individuals like them can do something so simple without harming their plants.

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There is one primary reason for this, and that is that plants may be fussy about the nutrients they receive and the ones they don’t. However, they don’t care where they come from.

Plants don’t even care if your liquid fertilizers are organic or man-made. They just want the nutrients in the right amounts.

When plants grow in the soil, the plants will be able to absorb anything that they want, but in hydroponic systems, the grower has to make sure all these nutrients will be available in the proper amounts?

For each plant, macronutrients and micronutrients are necessary for flourishing. However, the proportions of these required are very different in the types of crops you will be growing. There are several variations in these home-made formulations, so making one batch of one kind can deliver a very different proportion to that of the next.

You can create a liquid fertilizer solution from nutrient salts, and these may be easier because you can adjust your blend to the weight of the salts you add. If you do use these, you must maintain their freshness and dryness, since the moisture absorbed will affect their weight.

The other thing to be aware of is that you need measuring spoons, a decent set of scales as well as rubber gloves when mixing any commercial formulations. The crystalline compounds can either burn or have another kind of reaction on the skin.

Finally, the nutrients you buy will usually have the inclusion of additional pH buffers. Since you are in the process of making your own, you are going to need a digital pH pen and solutions of pH UP and pH Down.

While measuring your pH levels, you can see your EC levels may be out of synchronization, so one other device you may also need is an EC meter.

How to Make Different Kinds of Liquid Fertilizer

There are multiple ways to make liquid fertilizer. Some methods you may have close to hand, or you can decide to purchase which components you need and begin making your own.

In the following sections will be all the formulas and steps you require to make a few different liquid fertilizers for your hydroponic garden.

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Necessary tools for making Liquid Fertilizer:

  1. 5-gallon bucket
  2. Aquarium air pump
  3. Disposable filters
  4. Measuring spoons

Compost Tea/Worm Tea


  • Water for mixing – don’t use faucet water. Use rainwater or aquarium water if you have access.
  • 1 gallon of compost or 1 pound of worm castings
  • Aquarium air pump for mixture aeration
  • Disposable filters for straining the compost or casings


  1. Place the compost or the worm castings into a large bucket
  2. Fill the bucket with water and mix well, so everything is combined
  3. Set the bucket aside for approximately three days, however, keep the bucket out of direct sunlight so the slurry will not evaporate.
  4. Add an air stone and run while the mixture ferments for this period. The aeration breaks up the matter and helps nutrients spread through the liquid mixture.
  5. Stir the contents daily to make sure the nutrients spread through the mixture.
  6. Run the resulting liquid through disposable filters to filter out all the solids. You can use the resulting liquids to add to your reservoir for fertilizer.

You can continue making this in batches as you will require about half-gallon for every 50-gallons of water in your reservoir.

Sea and Animal Byproduct Formulation


  • 1 gallon of water as a base for the mix.
  • 1 ½ teaspoon of fish emulsion for nutrients
  • 1 ½ teaspoon of seaweed extract for nutrients
  • 1 tablespoon of blood meal for nutrients


  1. Add 1 gallon of water to a large bucket
  2. Add 1 1/2 teaspoons of fish emulsion
  3. Add 1 1/2 teaspoons of seaweed extract (You can use dried seaweed if not roasted)
  4. Add one tablespoon of blood meal as extra nutrients to promote plant growth.
  5. Stir well and use it as fertilizer for your plants.

You still need to filter this in case there are any large lumps in the blood meal. Also, if you use seaweed, you will need to let this steep a while before use. Tie it in a cheesecloth and let it sit before straining.

Fertilizer-Water Mix


  • 3 gallons of water
  • 2 teaspoons of nitrogen fertilizer
  • 2 teaspoons of phosphorus fertilizer
  • 2 teaspoons of potassium fertilizer
  • 3 tablespoons of Epsom salt, unscented


  1. Pour all the gallons of water into a large 5-gallon bucket (use rainwater or pond or aquarium water)
  2. Add the three fertilizers into the bucket and make sure there are no lumps
  3. Be sure the fertilizer contains both macronutrients and trace elements, such as copper, zinc, and molybdenum.
  4. Add Epsom salts to the water to provide magnesium sulfate. This is one of the more essential steps.
  5. Mix the solution until everything dissolves.  
  6. You can add this to your system when you next flush and are ready to mix your new batch.

Before adding, like the other formulations, it will require filtering before use. Any lumps can block your system unless you are not using a water pump.

There are many other formulations of fertilizers you can make, yet these above are proven to be beneficial to any system.

Liquid Fertilizer Growth Boosters

While the above formulations can help save some money in comparison to purchasing hydroponics nutrients, there are times when plants can do with that little extra boost.

This can be if they begin showing signs of deficiency, or the plants are at a different stage of their growth. The following liquid fertilizer boosters are straightforward to make and can be just the thing to help your plants when they need a little extra.

Deficiency Boosters

Calcium Deficiency

Plants that show signs of calcium deficiency can benefit from this simple addition.

Crush six washed eggshells in a pestle and mortar or a blender. Add to 1 1/2 liters of water with a few drops of hydrochloric acid. Let stand for 24-hours before filtering out the shells. Test the liquid to make sure it has a pH of around 5.

In the growth stage, you can use it with nitrogen-rich fertilizers. In the flowering stage, you can use it with fertilizers high in potassium and phosphorus.

Potassium Boosters

In the flowering stage, this can increase growth by 20%. This can help plants use sugars, carbs, and starches they absorb.

To make this, boil three to four banana skins in a liter of water. Add a little sugar or even better molasses. Let cool and use a few drops as needed.

Growth Enhancers

Coffee Ground Booster

Add used coffee grounds to water and let them soak for 24-hours. Filter and add the liquid to your tank during the growth stage. The bacteria that develop on the waste coffee grounds contain 2% nitrogen as well as many other organic nutrients.

Root Growth with Bean Tea

Beans and lentils are full of compounds called Auxins. These are fantastic for root growth along with stems and leaves as they reach up toward your grow lights. All you need to do is soak beans in water until they are hydrated. At this stage, blend them into a paste.

Strain this with a fine cloth. This is perfect for cuttings or seedlings to promote root growth.

Multipurpose Fertilizer

Take one small spoonful of Brewer’s Yeast and add it to a literof water. When this dissolves, it will produce potassium and phosphorus-rich liquid fertilizer. You can add this at any stage of growth for your plants.

Using Homemade Liquid Fertilizers

One of the most significant problems with making your own is that each time, you can end up with a different degree of nutrients in each batch.

However, when the blends are too high in the concentration of some nutrients. Your plants will be unable to absorb sufficient water. The salts will need to dilution, and if the nutrient mix is too high, your plants will start to shed water and not absorb it.

This results in the dehydration of your plants while the salts suck up the moisture from your plants. When you first start adjusting formulations, you need to do so with some restraint and caution. If you are wrong, you may destroy your entire crop.

Here are some common signs of nutrient deficiencies in your hydroponic plants.

  • Nitrogen: This produces plants with stunted growth that have more extensive root systems. Leaves may be smaller and light-colored. The growth will be slow.
  • Phosphorus: This will lead to stunted plants that have dark, discolored and dull leaves. Stems will be abnormally hard, and they will have a weak root system. Also, you will see a little branching.
  • Potassium: The older leaves will turn yellow and curl. Newer leaves fall off as they grow. The blossoms become dull, and the plant stems are soft and unable to offer full support.
  • Calcium: This makes the roots not develop much, and you have curly edges of the leaves.
  • Manganese: This leads to weak growth and poor flowering.

The only time you can be sure of the same levels is if you used powdered nutrients and mix them with water.

One other thing to be cautious of is that your plants don’t get any nutrient burn. Even with filtering, you can find your containers have sediment at the bottom. You need to be wary of this as it can quickly clog systems, especially your water pump.

Testing Your Liquid Fertilizers

It doesn’t matter which kind of nutrients you use for your system; you always need to check your system to make sure the TDS, PPM, and the pH levels are all in line.

The same issues can arise with homemade nutrients as they can with bought bottled nutrients, and the problems may manifest slightly different.

Here are the necessary procedural steps to test any nutrient mix you decide to make and add to your system. One thing you will note is the water is warm. This means it will be more in line with your system temperature when running, and it can help any powdered compounds to dissolve.

Test the pH of your water and the TDS/ PPM before you follow the next steps.

Your pH levels are sure to change when you add your compounds. Keep these initial readings because you will need them to find the precise concentration after you take your final reading.

With your measured out liquid fertilizer, add this to your reservoir and allow it to mix before you add any other booster fully.

Once you have added all your liquid fertilizers, let the solution stand until it sufficiently cools. With warm water, this should take around 2-hours. Once cooled, test the pH a second time and make a comparison with your first reading.

If it is outside the range that is right for your plants, you can adjust this with pH UP or Down until you reach the correct level.

You will need this second EC reading, as you will be diluting these mixtures at the time you are ready to add them to your tank.

While all the formulas for liquid fertilizer here don’t use many compounds, you can make liquid fertilizer from many of the same compounds as commercial farmers. These take much more experience, and you will need to adhere to the steps above.

Organic Liquid Fertilizers

Once growers begin making their liquid fertilizers, they may be thinking about making them organic. Most of the fertilizers above use compounds or elements that are already as good as organic. This again may make a grower feel better in themselves, yet their plants won’t care.

The issue with man-made and organic is that it can be challenging to reach the high levels of calcium and nitrogen needed to feed plants. The formulations provided here do their best, and there is a good chance you will need to make the boosters for supplemental feeding.

There is still a big debate on whether or not hydroponics can be organic at all. Using one of these, or any of the other liquid fertilizers is an excellent way to lean towards organic farming in time to make the switch when it best suits.

A good base for organic gardening is vermiculture, and with the worm castings, you can see this effective formulation pushes the meaning of organic to the limits.


These formulas may appear to be hard work for small amounts. However, the recipes can be scaled up so that you have sufficient liquid fertilizer for a couple of months. The upside with this is when you come to test because you will have a batch that is equal strength.

This doesn’t just make the formula easier to test, and it means your garden will be running the same with fewer fluctuations than ever before.

Making your own liquid fertilizer can seem to be hard work, yet the effort is well worth what you get out of it when your plants are blooming, and your crops have high yields just as if you were using regular store-bought manmade nutrients.

One thing which is often overlooked, when you make liquid fertilizer, is that you’re fruits and vegetables will taste better and won’t come with that hydroponic bitter taste some crops can.

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Understanding Conductivity Factor (CF) in Hydroponics

Many new hydroponic gardeners get confused with all the readings they need to take. With EC, pH and TDS, it can be boggling. To make it worse, there is another reading growers should be aware of.

CF and how to control it is can be daunting, luckily though, these readings are not so hard to fully understand.

Here, we will explain what CF is and how it can affect your garden. We will also see how it relates to other readings you need to take from your solutions

What is CF?

CF stands for conductivity factor, and like the EC of your nutrient mix, it is a way of telling you how weak or strong your formulation is.

If it is too strong, you can quickly overfeed your crops, and if it is, too weak and you can find your plants are suffering nutrient deficiencies.

To make things even simpler for new growers, the CF (Conductivity factor) and the EC (Electrical Conductivity) are basically the same thing.

There is one slight difference, and that is CF is a 10 x multiple of an EC reading. You may wonder why there is a need for another reading, which is the same as another albeit in a different format.

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It is true; a CF reading is just your EC reading and multiplied by 10. It can be used because it eliminates any requirement for a decimal point.

To simplify this, you can use the following:

  • 1 EC equals 10 CF
  • EC multiplied by 10 equals your CF
  • CF divided by 10 equals your EC

Understanding Your Target CF

When you purchase any hydroponic nutrients, you will find that the majority of suppliers give a target EC or CF. this will of course though assume that you are setting out with an EC/ CF of zero.

About your water, this can only come from pure water, which has a CF/ EC of zero. Water from the faucet contains minerals, and will vary depending on if it is soft water, or it is hard water as you can see here.

Soft Water – is generally CF 2 (or EC of 0.2)

Hard Water – is generally CF 8 (or EC 0.8)

There are two steps to find out your actual target CF.

  1. Take a reading of your base water to find the CF
  2. Add this reading to your manufacturers target CF

As an example, if you have water from your faucet, and it is soft water. You will have a CF of 2. If your nutrient manufacturers target CF is 16, you will have an actual target CF of 18.

When manufacturers offer these target CF’s, they will do so for plants that are at various stages of growth.

  • Young plants – CF of between 4 to 10
  • Established plants – CF of between 10 to 18

Just like EC readings, an ideal CF will vary. The CF can be seen as your nutrient to water ratio. This means if plants are hungry, they will require more nutrients, and likewise, if they are thirsty, they will take up more water.

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Just like other readings in hydroponics, there can be many factors, which affect things. With this, there are many things that can make crops and plants thirstier or hungrier throughout their life.

  • Types and size of crops and plants
  • Season and temperature of grow room
  • Water hardness used
  • Method of growing

Taking a reading may not deliver the chance to find an exact CF. It is for a reason that you will need to take readings at regular intervals.

Just like your pH levels, you will find your CF levels go up or down, and you will need to respond to bring these back in line.

Checking Your CF

To test your CF in your solution can be much the same as taking any other reading. There are various meters, which can take readings of CF along with EC, pH and others. Most of these require manual calibration in comparison to one device called the Truncheon by Bluelab.

These are factory calibrated, but they do come with a higher price tag than the other digital meters.

  1. Leave a pale/ bucket of water from the faucet outside to dechlorinate for at least 24-hours.
  2. Use your CF meter to take a background reading
  3. Add your nutrients at the manufacturers recommended doses
  4. Once they have dissolved and settled, take another reading
  5. If it is too high, add water to lower the CF level

One thing that is worth remembering is that a one-degree rise in temperature can raise your CF reading by 2%. Because of this, you should aim to take your readings at the same time every day.

Correcting CF Levels

Ideally, you will want your CF levels to remain the same as your plants feed. If this happens, it means you have your CF set correctly.

However, in the instances, it has gone up or down, the first thing not to do is panic; you can adjust this as required.

When CF levels rise, this means plants are taking up more water than you expected them to. This can happen when the environment is warmer, and plants become thirstier. This will leave the concentration of TDS increasing in strength.

To lower this, you should top off your tank with plain water only. This is the standard way of making sure your plants don’t suffer from nutrient burn.

If your CF levels drop, many growers will advise in adding more nutrients to raise these levels. However, there are more growers who advise to never add nutrients at this stage. It is better to let plants have access to less than to begin over feeding them.

If you want to be sure they get enough nutrients, the easiest way can be to flush your tank and add a new batch of nutrients with the correct CF.

Warning Signs Your CF Levels are Wrong

The signs that levels are not correct are very similar to EC levels that are out of balance.

If you are underfeeding, you may see

  • Phosphorous: Stems and parts of large leaves begin to purple
  • Nitrogen: Leaf tips yellow and begin moving toward the step of the plant
  • Potassium: The yellowing moves from the tips toward the main leaf veins

If you find out you are over feeding, you may spot the following signs

  • Your plants leaves begin curling downward
  • Leaves have stunted growth and are too small
  • Leaves are dark and lack any vibrancy


There may be a good many growers who find out that CF isn’t used very often when taking readings of their solutions. It is however better to understand what it is, and how to calculate it if needed.

It is good to know that one CF is equivalent to around 65 PPM (Parts per million), and the EC with be around 650 PPM as an equivalent. Because there are lots of confusion with these figures, new growers follow the simplest of methods, which works for thousands of gardeners with hydroponic systems.

Keep things simple and run half-strength solutions in the vegetative stage of growth. Once your plants reach the fruiting and flowering phases, you can then deliver a full strength set of nutrients when they can handle them.

Aside from this, flush your tank and replenish with new nutrients on a regular basis, and you will see great results.

Associated Questions

Why is a CF/ EC level important? While some growers don’t use these readings, knowing what they mean does allow you to understand more what happens in your system. Your CF and EC can stay the same, or go up and down. If plants are taking up water, then you should always see a CF that increases as nutrient concentrations increase.

What does PPM mean? Parts per Million means one part of your nutrients in one million parts of your solution.

Which is the best meter, an EC or TDS meter? Many new meters can read multiple things and will make the conversions for you. However, it does depend on your plant nutrient recommendations. If your scales are in EC/ CF then a meter which reads these, is ideal, however, if you are using PPM, then a sodium chloride TDS meter will be easier to use.

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4 Common Hydroponic Plant Problems (With Solutions)

It doesn’t matter how experienced a hydroponic grower is, there can be many occasions when they have plant problems and they need fixing. This is worse for new gardeners because they may never have faced these issues and wonder how they can fix them.

Here we will look at some of the more common problems, which occur with plants, and how growers can set about tackling them. What are the most common hydroponic plant problems? Some of the most common problems come from diseases, pests, grower mistakes and problems with the system environment.

Growers are tasked with making sure their plants have the exact amounts nutrients, water and light. This goes a long way to make sure there are no deficiencies yet it can still happen without a grower knowing. All of these factors play a very important role, and a grower doing something in response to another action can have a reaction in a very different area.

We will now look at the key problem areas in plants and how you can go about resolving these.

Hydroponic Plant Diseases

One of the more frightening problems growers face is plant disease. They may think there is little hope and in their mind, they are more than likely thinking of tossing out their entire crop.

In some cases, this may be the case, yet this is in the extreme times. Most times, there is something growers can do to resolve the plant disease issue and save their plants.

A grower should already understand, a growing room needs to be a sterile environment, and even entering it in dirty clothes can be enough to trigger some of these diseases. The same goes for necrotic plant tissue that stays in a system. This dead tissue rots and is the ideal starting place for deadly bacteria and pathogens.

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Here are the primary plant diseases growers need to be wary of:

Powdery Mildew – This stunts plant growth and reduces yields considerably. Once it gets into a garden, it can be a struggle to prevent it from spreading. When you see this, leaves will be covered in white blotches as if someone has dusted them in white powder. Two key factors allow this to infect plants, first is the strength of the plant, and second, the environment.

The best speedy solution to fix this is remove infected leaves, and ensure there is lots of airflow and lower the levels of humidity. Plants, which grow stronger, have thicker cell walls, and it is this, which prevents powdery mildew from sending down its feeding tubes. You can also rinse the spores off the leaves, but give your plants the best chance of drying afterward.

Downy Mildew – This kind of mildew is found more on agricultural plants rather than the powdery variety, which is found on flowering plants most often. The tops of the leaves will be covered in yellow patches; while underneath there will be a fain frosting of gray, violet or blue. To stop this, you will go through the same as above such as pruning infected leaves and tissue, and making sure plants have lots of room for good airflow.

Steps to Prevent Plant Disease

Prevention is the best cure for plant disease. Even with these, a grower can face many more such as Gray mold and other varieties.

There are a few things you can do to make sure your plants stay clean and healthy.

Clean Clothes – It can be easy for disease to travel around on your clothes. Spores are microscopic, and can latch onto anything before falling toward their prey when they feel the time is right. Grow rooms should be sterile, and the best way to begin this practice is wear clothes which are somewhat clean and haven’t been used for working in the outdoor garden.

Keep a Clean Grow Room – There are many different molds and mildews, we have only touched on a couple, yet they can all find their way into your grow room. Keeping a clean area is vital as is making sure any ventilation is properly filtered, and there is not dirty or dead plant debris laying around. Any tools need wiping down at regular intervals, and there should be no sign of soil anywhere inside your growing area.

Algae Plant Problems in Hydroponics

Because the spores of algae are microscopic, they can enter your grow room in the same way as the spores that lead to plant disease. However, in hydroponics, the conditions are perfect for algae growth because they are so similar to plants.

There are a number of growers who say to starve algae of what is feeding it, yet doing this means you will be starving your plants of the goodness they require.

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It is more a case of what are the degrees of algae in a system? This will determine the level of plant problems growers’ face. If you catch algae growth early enough, it won’t be as big a problem, yet the longer it goes on, more significant factors take place.

First, there is a drop in nutrient levels as the algae uses these for its own growth; second, the amount of dissolved oxygen is reduced. From here, you can have plants suffocating and then there will be the onset of root rot.

Preventing Algae in Hydroponics

Preventing algae can be an ongoing saga, and it will mean keeping your growing area as clean as possible. Algae doesn’t like dry surfaces, so this is why you only see it around the water line in your system. Commercial algaecides are of little use, and there is no better way of ridding a system than flushing it and giving a good clean.

It is best to do this when you are changing your batch of nutrients, because you will then know your system is as clean as it can be.

To do this, drain your system of liquid. You can then use hydrogen peroxide at a ratio of 3 milliliters per gallon of water. Before topping your system with this solution, check for debris and remove this. Top your system above your regular water line and run this peroxide solution for up to six hours without plants. Drain and rinse then drain again, and wipe down every surface you can reach.

Two ways to slow the growth of algae is to use opaque materials on your system. Light is one thing that algae loves as it tries to grow in your tank. Second is to cover any exposed water. This is to slow the algae from entering your system as well as blocking out light.

One other tip is to use a UVC light in your filtration system. These can be costly, yet they can kill microorganisms. A more natural way is to administer up to 10 drops of grapefruit seed extract per gallon of water, these low doses don’t harm plants, yet they are effective at fending off algae.

Hydroponic Plant Problems from Pests

There are many who think that hydroponic gardens are free from pests however this isn’t the case. While they are free from some, it is nearly impossible to keep pests from an environment that is as warm as an indoor growing area.

Plant pests are unfortunately developed to travel between crops even if these are indoors. Growers do need to be vigilant because an infestation of pests can quickly ruin crops before they are aware of the problem.

Here are some of the more common indoor garden pests growers can encounter.

Spider Mites– Spider Mites are probably the most common of all the indoor garden pests. Because the mites are so small, you probably won’t notice them into its too late. There are two very easy ways that you can spot spider mites. One way is to keep an eye out for a webbing material that kind of looks as if it came from a spider. The second way is to wipe the back of the leaves with a cloth and see if there are any traces of the bugs on it.

Thrips- Thrips are a hard pest to identify, but with a good eye, you will notice small black speck on your plant’s leaves. The leaves will usually turn brown in color and become dried out.

Aphids– Another name for these pests is plant lice. They will be either green or black in color. The aphids will severely weaken your plants by sucking all of the juices out of them. This will cause your leaves to turn yellow and then brown. They are mostly located on the stem.

Whiteflies– They resemble small moths that are all white in color. Their color makes them very easy to find, but they can fly, so they are very hard to catch.

Fungus Gnats- Although the adults of this species aren’t harmful, the larva form can be very deadly for your plants. These pests can slow down the growth of your plants by feeding on the roots. These appear to be small white worms in the growing media.

Plant Pest Prevention Methods

Although there are many technologies for the prevention of pests, some of the better ones are still the older natural ones. One of the favorites of growers is the compound neem oil. This has been used for centuries, but has only been available in the past few years in an easy form for application.

Neem is also a longer-term approach because it is an insect growth regulator. This means it will work better over the long-term to break the life cycle of the insects. The one good thing with neem is that as it is a plant extract, it is nontoxic in smaller doses, yet care does need to be taken.

Sticky Traps are another great means of controlling these pests. When you hang sticky traps around the room, you can trap the pests, and this will make it easy to identify them. Blue stick cards are good for catching thrips. Yellow cards attract fungus gnats and whiteflies. It is important that you make sure some cards are at the soil level and the medium level of your plants.

Another natural means of protecting plants against these pests is the introduction of beneficial pests. Outdoor gardeners know all too well about these and they can also work for indoor gardens.

Ladybugs are a prime example, as are lacewings, preying mates while there are also Hypoaspis and Encarsia Formosa, which eat greenhouse whiteflies, fungus gnats and springtails. The problem using these in some gardens is that they themselves struggle to survive over long periods.

Nutrient Deficiency Plant Problems in Hydroponics

New growers may think there are many plant problems such as the above, yet the one thing they are delivering to their plants can be one of the major areas where there are plant issues.

Either delivering too many nutrients or not enough can lead to nutrient deficiencies. This can leave gardeners frustrated, as they are not sure what is causing their crops to suffer. Symptoms can be saying one thing while the cause is actually from something else.

Nutrient Lockout can come from many areas in a system. Water can be a culprit especially if pH levels are out of the ideal range. It is vital for growers to know the ranges that are suitable for good plant growth and the things that can affect this. Faucet water can have a bearing on pH, as there are many compounds in this water depending on the region you live.

Heat stress can also lead to nutrient deficiencies as can an insufficient amount of lighting.

Growers need to know how to diagnose deficiencies before they can fix the issues. Leaves should be an even color all the way across and they should have a uniform shape. Once leaves begin showing a shape, which is not the same as older foliage, or the colors are patchy then these are the first signs there is a problem.

There are many signs of nutrient deficiency yet most come from the macronutrients because they are the ones plants use the most of. To fix and prevent these is not as hard as it appears if they are caught soon enough.

Fixing Nutrient Deficiency Plant Problems in Hydroponics

Two of the main areas growers need to attend to when fixing these issues are the pH levels. It is vital to monitor these levels daily, as it is to measure the EC levels of the solution. This is straightforward with a good digital EC tester, and a pH testing device.

Growers should also understand that just because a plant is showing signs of a nutrient deficiency, it doesn’t mean their solution is lacking this nutrient. Phosphorous levels, which are too high, can block plants taking up other nutrients.

An iron deficiency can be something as simple as a nutrient solution being colder than the recommended temperature. The range of temperatures for a solution should be around 68 and 72 degrees Fahrenheit. Iron deficiencies can also be caused by a solution, which is rich in manganese. This shows why adding more nutrients isn’t necessarily the best approach.

The best approach for fixing any nutrient deficiency can be to flush the system. It may sound counterproductive to take all the nutrients away from the plants, yet in almost every cases, the solution doesn’t lack the nutrients and the deficiency is caused by a secondary factor.

To do this, remove any leaves that are showing large signs of discoloration or they are badly damaged. In severe cases, you may need to go back as far as the stem. Removing any leaf matter that may die is vital because if this rots, it allows pathogens to enter the system.

Pots and growing medium should be flushed with pH-balanced water to remove any salt buildup, and then the system should be topped up with fresh water only. At this stage, it should be run for a period of 24-hours before measuring pH and EC levels again.

Once both levels are back in line, you can mix a new batch, yet it is advisable to only use a three quarter strength of the manufacturer’s dosage. One final addition can be some organic liquid tea as a supplement. This is beneficial to your plants without increasing certain nutrients to the point of causing lockout.


Growers do have many things to contend with, and in some instances, they may wonder if it is worth having a hydroponic garden because of these problems.

While these can hit at any time, once the right precautions are in place, the actual chances of these problems hitting a garden are dramatically reduced. Growers quickly understand how their systems and gardens work, so they will be taking precautionary measures as a matter of course.

A hydroponic garden is worth the extra effort it takes to control these problems, because if it weren’t the number of growers would be declining rather than increasing.

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9 Vegetables You Can Grow In Hydroponics (with pictures)

Hydroponics is a booming means of growing produce at home. New gardeners who are thinking about this often wonder what are the best crops to grow, which are easy and will deliver the best yields.

There are many reasons why individuals are turning to this way of growing, and it doesn’t matter if it is because they want to help save the planet, or cut down on their grocery bill. Hydroponics is a great way to do this and much more.

While not every vegetable thrives in a hydroponic environment, many do. So here are the top, nine any new hydroponic grower can grow into their system. Some are very easy, while others take a bit more effort and space, but nonetheless, all of them are worth adding to any hydroponic garden.

Here, we will look at each of these top nine hydroponic vegetables and which systems are best suited to their growth.

Best Vegetables for Hydroponics 


Leaf lettuce makes an outstanding option for hydroponic cultivation. It grows in the simplest systems and requires minimal attention. As you grow, you can harvest the external leaves from your lettuce, meaning you will end with a prolonged crop of fresh, crunchy lettuce. As the leaves are cut, the internal leaves will grow rapidly to take their place.

There are many varieties to choose from, and most of them are suitable for growing this way. The more common types are:

  • Tom Thumb
  • Boston
  • Iceberg
  • New York
  • Romaine
  • Buttercrunch Bibb
  • Simpson
  • Waldman’s Dark Green
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Lettuce are suitable to grow in NFT, DWC and Ebb and Flow systems. If the temperature gets too hot for them, lettuce can bolt and may taste bitter. They are a cool weather vegetable and like temperatures between 50 and 70 degrees fahrenheit. Lettuce are also fond of high nitrogen levels.


Kale is one of the top vegetables that is grown because of its health benefits and is delicious flavor. This can be germinated from seeds and once it begins growing, it can handle a wide range of temperatures from 45 to 85 degrees fahrenheit.

From seed to harvest takes around ten weeks, yet like lettuce, you can pluck up to 30% of the plant leaves. Again, new leaves will grow back and you can extend the time your crops are in your system. If you transplant, you can cut the time to harvest down to around 6-weeks. One good thing with kale when grown indoors is that many pests don’t target it. Aphids being the primary culprit, yet they can suffer from powdery mildew.

The main varieties are Curly kale (common type sold in grocery stores), Lacinato kale (sweeter and have longer leaves), and Red Russian Kale.  This variety is the sweetest you can grow and has a reddish appearance.


Being another cool weather crop, this is perfect to grow along with lettuce and kale. Any temperature over 75 degrees fahrenheit will see the plant suffer. It can be grown from seeds and many hydroponic growers will place their seeds in the refrigerator for up to three weeks before planting. This creates a plant that is hardier and thus a healthier plant. They do like around 12 hours of light daily, however, because they are cool weather plants, T5 fluorescent lamps may be the better option for lighting.

When it is almost time to harvest, you can lower the temperatures because this has the effect of making the crop sweeter. However, because of this, growth will slow. It is advisable to go for quality over quantity to prevent a bitter tasting leaf.

Most systems are suitable for spinach, but just remember to plant them a few weeks apart so you can have continual harvests. A raft system can be perfect for these as it can be for lettuce and kale as well.


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Growing cucumber in hydroponics can be so rewarding. These vegetables love the conditions they are given. Warmth, nutrients and lots of moisture are perfect. Growers are amazed at the yields because they quickly become one of the highest yielding vegetables you can grow.

The ideal temperatures for optimal growth are just outside the ranges that the above leafy greens like. Saying this, they can grow in a range from 60 to 82 degrees fahrenheit. This makes them ideal for growing alongside the next two crops in the list.

Cucumber likes a pH of 5.8 with an EC between 1.8 and 2. Growers can find seeds expensive for a good hybrid strain, yet when you see what fruits one seed can bear once it is growing, this cost per seed is more than justified.

The hardest thing with cucumber growth is they are vining plants and will need trellises. This makes them more suited to flood and drain or other bucket type systems, where there is plenty of growing medium to help support. This being said, coco coir is one of the better mediums to use as long as the plants are supported well.

Be on the lookout for pests like mites, thrips, whiteflies, and aphids. These insects love to take advantage of cucumber crops.

Nutritious Tomatoes


When growers move on to tomatoes, it shows they understand their system and wish to go on to the next level. Having a continual supply of fresh tomatoes is what hydroponics is all about.  

These are a warm weather plant and like the temperatures like cucumbers. They do however prefer an EC level that begins at 2 and goes up to 5, so any system will need to be separated to allow tomatoes to grow on their own, or at least with other plants that like this level.

The ideal pH is between 5.5 and 6.5 and the temperature is between 58 and 79 degrees fahrenheit. The upper end of the range more preferable.

They can be planted from seeds, yet cuttings or seedlings are advisable because it takes too long to grow fruiting plants from seeds. There are many varying types, yet the vining varieties are popular because they are easier to control and harvest from.

Tomatoes as if cucumbers require trellises so they can grow upward, and they will deliver a steady stream of fresh fruits you can part harvest.

Tomatoes can suffer from various pests and diseases like spider mites, aphids, mosaic virus and much more. One other thing that can occur depending on tomato variety is they can be prone to splits. This is when the inside of the tomato grows faster than the skin. This often happens when they take up too much water in a short time.


Although most root vegetables are not ideal for growing hydroponically, radish are different. These are a cool weather crop so they can accompany the first few plants in the list. They also mature rapidly, and just happen to be one of the easiest plants to grow.

The pH is bets around 6 to 7, and the temperatures between 50 and 65 degrees fahrenheit. If you are growing a longer radish variety, these can withstand a bit more heat than the short bulb kinds. EC levels should fall between 1.6 and 2.2.

Lighting requirements are minimal, and at least 6-hours are needed. Optimal levels are between 8 and 10 hours of light.

Seedlings are not recommended, and they are better grown from seeds. From germination to harvest can be as little as three or four weeks. Add to this, if you stagger your planting, you can harvest all the way through the year. This cool-weather vegetable grows excellent in hydroponic systems where the temperature hovers between 72-76 degrees Fahrenheit.

The most common problems with radish is they can easily bolt if they are not kept mist, and if they are too wet, they can suffer from root rot.


Nearly every kind of bean can be grown in a hydroponic garden. There are hundreds you can choose from yet the most common are runners, string, pole beans and bush beans. These are easy maintenance and very productive for the effort which goes into growing them. Some types do take more effort because they are climbing/ vining plants so they will need support trellises.

When growing from seed, they are speedy germinators and can take less than two weeks. You may even see some varieties start in as little as seven days.

When growing and you can see they have two true leaves, then they are the right size to go into your garden. Depending on your system type, although ebb and flow being the better option, however, a drip system is also ideal. Plants should be planted around 4-inches apart when they are the bush variety. Pole beans should be spaced a little wider apart at around 6-inches.

One good thing with beans is they self-pollinate. Growing medium should be loose so hydroton pebbles or a mix of perlite and vermiculite are good options and have several advantages. With a neutral pH, perlite won’t affect your levels and expanded clay pebbles offer enough moisture and oxygen to the roots.

Twelve or thirteen hours of light is enough, and the daily temperatures should be between 70 and 80 degrees fahrenheit. If a temperature falls below 60, or rises above 60, then there will be a knock-on effect to the plants pod growth.

Beans don’t need many nutrients and when spacing them apart when planting, you can have a continual harvest. This can come in as little as 50 days for each plant.


Peppers are a great addition as they can be grown in any season. Not just this, but yields growers can experience are much larger than if they are grown by conventional means. This means fruits are larger and a better quality as the plants are delivered what they need to allow them to grow to their genetic potential.

Ebb and flow systems are best suited to this kind of vegetable, although they can be comfortable being grown in others which have a good base of growing media for support. These plants can grow quite large, so they need additional spacing of between 7 to 9 inches between plants. This can limit a pot to two plants only.

Lighting needs to be around six to eight inches above the plants and will need adjusting as they mature. If the bulbs are closer than this, it can cause scorching, and if further away, it can affect the yield or potential growth.

Lighting needs to be up to 12 hours per day, and no less than 10. Additionally, they will need sufficient amounts of nighttime hours as well. Daily temperatures need to be between 73 and 80 degrees fahrenheit, so they are perfect companions to be with cucumbers and tomatoes.

Extra attention is required during their growth where stem buds need pruning as the plants are about 8-inches in height. This helps the plant devote its energies into larger fruits than lots of smaller ones.

The pH levels need to be between 5.5 and 7, and the EC should fall in the range of 3 to 3.5.


Celery can be one of the harder vegetables to grow in a hydroponic environment, but it doesn’t mean it’s impossible. Celery seeds take up to two weeks to germinate, which is pretty long compared to other vegetables. A quicker alternative is to use the stalk of celery you purchased from the store.

If you take the stalk and cut 2 inches from the bottom, then place the base in a plate of room temperature water, it will actually start to grow after only a week. Celery needs a lot of water, so the proper system to choose would be a deep water system. Along with germinating seeds, harvesting celery can take up to 4 months total after the seeds are planted.

Celery likes a pH level of 6.5, and the EC level of the nutrients should be 1.8 to 2.4. This can be an accompanying plant in a grow room which is geared up for lettuce and cool weather crops. The daylight temperatures should be between 58 and 80 degrees fahrenheit. Lighting isn’t extreme and they only need around 6 hours per day.

It can take a long time to maturity and harvest, and they can test a grower who will need patience, however, growing this crop can be one of the most rewarding considering how expensive it can be from the supermarket.

Benefits of Hydroponics to Grow Vegetables

Using hydroponics to grow vegetables can be highly beneficial, especially in regions where conditions are not suitable, or those times of the year when nothing will grow. Many of the crops above can be grown around the year, or you can grow these while planting any of the many others, which aren’t on the list in a different growing season.

There are countless benefits no matter what you choose to grow, and here are a few you will see:

Larger Yields

Hydroponics can’t make vegetables grow larger than their genetics lets them, however, they can grow to their full potential and in a much smaller space than they can in soil. Being able to control the nutrients and pH levels in the water also ensures only optimal growth for the vegetables leaving little room for failure.

All Year Round Crops

As we just saw, because the gardener is in total control, they can use artificial lighting and warner indoor growing conditions to grow through the year. Crops that are out of season become expensive when they are shipped in, but having them a few steps away from your kitchen makes all the difference.

Less Space

Hydroponic systems can be built almost anywhere. They can be indoors away from any natural light, or they can be in outdoor areas undercover, or in a greenhouse in the garden. However, with a much smaller space, they can churn out many more crop harvests which is possible than if the garden was in soil.


When a hydroponic garden is up and running, they can easily produce more than enough food for a large family.

While some crops are not suited, there can be little need to purchase some vegetables ever again. Many growers begin by just growing for consumption, yet as they go along they find they expand and need to begin getting rid of vegetables because they are producing too many.

Family and friends will be thankful of tasty fresh vegetables, yet there are the shrewd growers who turn their gardens into small home enterprises.

The vegetables above are just the tip of what is possible with hydroponics. The choice of what you grow is up to you, but just the ones above mean you can have a wide variety of choice. Start with these and as soon as you gain more knowledge, or you find you have that extra little space, you can expand and tackle herbs, strawberries or anything else you find is hard to come by where you live.

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How Big of a Reservoir Do Hydroponics Need?

When any grower begins looking at building a hydroponic system, one of the main components will be the reservoir. Because the entire process revolves around water, this will need a home that is worthy of the life giving essence that the water provides.

The question arises for many growers because they may be trying to figure out what will fit where in their designated growing area. “How big of a reservoir do hydroponics need?” There is a general rule for this, which we will see, yet there is much more to determining the size of a nutrient reservoir than just having one of a specific size.

Carry on reading for all you need to know about hydroponics tanks and how you can be sure you have one that will meet all the needs of your system.

Do You Need Hydroponic Reservoirs?

Reservoirs are a fundamental component of any system. If it weren’t for these, there would be no place to put the water and nutrient solution. There are a few aspects to go through rather than just thinking a reservoir of a certain size is good for a given number of plants.

One of the first to know is that the size can change depending on the type of system you are looking to run. However, no matter what system you are using, the consensus is that the bigger the reservoir, the better it is for your system.

The reasons for this are a larger tank can help with pH swings, nutrient solution fluctuations and the depletion of oxygen. As soon as any of these factors are affected, then there is a knock on effect with the rest of the system and the plants.

You can add to this how the environment plays a role in the operation of a reservoir. Plants will change their uptake of water and nutrients depending on the environment, and if the humidity is lower than the ideal 60 and 80 percent, and is lower than forty to fifty percent humidity will cause plants to take up much more water to compensate.

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If it were just a basic calculation to determine the reservoir size, this would be easy. As a rule, there should be the following:

  • Small plants: 1/2 gallon of water per plant
  • Medium sized plants: 1 – 1/12 gallons of water per plant
  • Large plants: 2 1/2 gallons of water as a bare minimum

Although these are the recommendations, many seasoned growers will double these volumes without a second thought just to be sure.

How Do Systems Use Reservoirs?

Here is a quick look at the different systems and how a reservoir fits in with their design.

  • DWC (Deep Water Culture): Plants are suspended over the top of the reservoir. The solution will be highly oxygenated as no water pump is used.
  • Ebb and Flow: The reservoir sits under the flood table. Using a timer, this is flooded periodically. Once the timer cuts off, then the solution drains back to the reservoir.
  • Drip Systems: Reservoirs sit lower than the plants. A pump will feed solution through small tubes where it drains through the growing media and makes its way back to the reservoir using gravity.
  • NFT (Nutrient Film Technique): A thin stream of water is continually pumped into the highest point of troughs or channels. Plants are suspended over this so their roots can hang into the solution. Gravity is the usual means of returning the solution back into the reservoir.
  • Wick Systems: A thick rope will sit in a reservoir and feed up to the growing medium in a container sitting on the top. Plants will be fed by this wicking action, which delivers nutrients upward.

The Roles of Hydroponic Reservoirs

Here are the areas where reservoirs help to keep systems running at their best. As we have just seen, each system can use their own reservoir in a different way. However, all the following will be common, regardless of the system, the plant type or the location.

These few areas are what makes your system tick and stay healthy.

Nutrient Preparation

Your reservoir is the ideal place where to mix your nutrients. Some growers may mix in a separate container and then add to the reservoir, yet this makes little sense to add more work into the equation.

In an ideal world, you should have a spare reservoir, and this is where you will be mixing your next batch while one is in use.

Water Oxygenation

Without oxygen, plants die and will die quick. Depending on the system type, these solutions need lots of oxygenation through the use of an air pump. This then has tubes running into the mixture, and air stones or air diffusers convert this into tiny bubbles, which the water absorbs.

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While some of the systems use the water cascading back into the reservoir, this doesn’t deliver as much oxygen as a good air pump.

Concentration of Nutrients

As water is taken up by your plants or water levels drop by environmental factors. This means the concentrations of the nutrients increases. This will be very different from when you first mixed the batch, and will make it harder for plants to absorb what they need in the right amounts.

Your solution will need continual testing and adjustment as is required. Yet, the larger your reservoir, the rate at which the solution changes concentration is somewhat diminished. This can help reduce the amount of testing, and space out the intervals for replacing solution.

A good EC (Electrical Conductivity) meter can take a quick reading and let you know the levels of nutrient concentration. There is no way at present to determine what levels of each nutrient there is in the solution.

Ease of monitoring and adjusting solution pH levels

Just like EC levels, the pH of your solution will fluctuate. This can be from a change in concentration or there is a change in the temperature. Holding a pH in the desired ranges is vital for the health of the plants.

When you have a change in pH, this can lead to nutrient lockout or nutrient toxicity if it swings the other way. The larger the reservoir, the slower the rate of change of your pH. This makes testing more straightforward and not required as often. You can find adjusting pH is easier when there is a larger amount of liquid.

Solution Temperatures

A small reservoir can heat up much faster than a larger volume of water. Plants like temperatures between 68 and 75 degrees fahrenheit for their solution. It doesn’t matter if you live in colder areas or warmer, this larger volume of water is easier to control once you heat or cool it.

One sure way to help with maintaining solution temperatures is to use insulated reservoirs. These will help even more in keeping the temperatures stable without the use of a hydroponic water chiller or heater.

Reservoir Considerations When Choosing

Before purchasing any reservoir, there are some things to consider aside from the above. While all tanks may appear appropriate, this isn’t the case.

In this section, we will look at all the factors, which can determine your final choice of reservoir for your hydroponic system.

Reservoir Construction

Many gardeners construct their own systems. This leaves the choice of materials for their reservoir very different from if they were purchasing one. While it leads for lots of creativity, this is often done more for cost saving.

Large plastic totes can hold massive amounts of water, and thus can be a viable solution. However, once these are filled, it can lead to issues, which are not noticeable in the beginning.

Once these containers get warm over time, they begin to deform and bulge outward. There are many reservoirs, which are made from durable and sturdy materials that are a better choice. Barrels or large picnic coolers can be great options, and in most cases, they will be made from food grade materials such as polyethylene.

Reservoirs Need Lids

Depending if you construct your own reservoir, or purchase one specifically will determine if it comes with a lid. While these don’t appear to be too important, they are in fact crucial for a couple of reasons.

A lid on your tank can reduce the evaporation of your solution, this helps maintain the EC and pH levels to what they should be.

Reservoir Color

Aside from a lid preventing evaporation, there is the fact that as light begins hitting your solution, there will be algae growth. Algae can deliver a whole host of issues like depleted nutrients and oxygen from the water.

The time between cleaning this growth from your tank can also reduce. While dark colors are a recommendation to prevent light seepage, these can absorb heat from grow lights. Covering tanks in silver foil or insulation can help keep light out and keep your solution cool. It is worth noting that warmer solutions can’t hold dissolved oxygen as well as colder solutions

Tank Location

This can depend on the kind of system you are running, but not only that, once they are full of water, there is no way you can relocate them.

Your reservoir will need to be out of any direct sunlight and it should ideally be close to a water source and a drain. This can make topping off and cleaning that much easier. One other thing that may have a bearing on this is the system type.

Many tanks sit under the bed of the system. Accessing the tank while the garden is in use can be very difficult. There will be hoses, pumps and pipes all over the place, which can be hard to dismantle to gain access. There is also then the consideration of how close the tank is to the grow lights. Hence the dark color and the silver insulation.

Care and Cleaning of Nutrients and Reservoirs

A reservoir and the solution it contains will only be as good as the care and attention it receives. It isn’t possible to fill one and then expect everything to be fine until it is almost empty. Here are some things to know about the care and attention for both elements.


There are many methods of testing solutions to be sure the levels are correct. While you can use manual means of doing so, these are not as effective as meters, which can make these readings in a much shorter time.

There are expensive automated means of doing the same thing, yet meters are not worth anything if they are not used. It is possible to purchase multi-purpose meters that are capable of taking readings of different elements like pH, EC and the PPM/TDS.

Many gardeners now use this kind because of the timesavings when testing. Not only this, but they are more accurate that manual testing means. One thing to be sure of is that any device you purchase can have manual calibration. This can prolong their accuracy and their life while reducing errors.


We have seen how vital dissolved oxygen is for plant health. The best ways to do this are through air pumps and air stones. The benefits are still being seen, so it is better to have more oxygen in your water than too little.

The other plus side of this is it prevents water stagnation and keeps nutrients being continually mixed and stimulated. This aeration can actually help with the nutrient uptake by your plants, and thus helping promote plant growth.

One area, which may not be seen by new growers, is that this aeration can help prevent any development of pathogens. Rather than any anaerobic bacteria forming, there is the growth of many other organisms that are beneficial.

Topping off Tips

Every grower has to top off his or her tank at some stage. Up until this stage, there will be lots of testing and waiting. However, levels will begin to drop the longer the system is running. We saw that nutrients strength increases because water take up is higher than nutrients.

This means that water needs adding to make sure plants have enough, and to dilute the nutrients before they become toxic. However, there is only so many times you can top off a hydroponic reservoir before the nutrient solution becomes too weak, and you are in need of mixing a new batch.

When first filling, you need to mark the high water level on the inside of your reservoir. This will need checking daily, and you can top off up to that level as required. This happens every few days rather than daily.

While doing this you will need to keep a check of how many gallons, you add. A good rule to follow is that once you have replaced 50% of the original volume, then this is time to consider flushing the system.

Reservoir Flushing

It doesn’t matter how large and how good this larger volume of solution is at buffering changes in the nutrient levels or the pH. There comes a time when you top off the the extent that the solution is weak, there is debris in it, or you are having issues with nutrient deficiencies you just can’t work out.

Having a clean tank is the ideal way to solve most problems, and it is the only time you know what your levels are. There are long conversations and debated when the best time for system flushing is, yet you can find that even if there is no real right time, there is definitely no wrong time.

It can be as little as a few days before your levels start changing from the ones you set, so it is easy to see why this system flushing occurs on a regular basis. Some gardeners may flush weekly, while others recommend bi-weekly. This is true for vegetables, which can take on a bitter taste through too much nutrient absorption.

Hobby gardeners can follow this and flush more often than not. This can resolve issues from beginning without affecting their plants.


As we can see, there is no real upper limit on size of hydroponic reservoir, yet being realistic does come into it. The main thing to consider is that you don’t choose one, which is just the right size or smaller. This can leave with continual issues you need to deal with, and you have no way to turn to offer a solution.

You can see why gardeners come up with the recommended size by the number of plants and the volume of water for each plant before doubling it. These buffers can make all the difference between healthy crops and a failed crop.

With the reservoir, that is the ideal size, and if possible, a second where to mix and use as the other is out of commission can lead to less downtime and a healthy yield from your garden. For the gardeners who can’t afford or fit in a second tank. All the above information should be enough to make sure their primary tank is large enough and cared for to give a healthy system.

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How Often Should You Fertilize Hydroponics?

One of the main questions which catches new growers out, is that of how often they fertilize their hydroponic system. Once their systems are up and running, this frequency can be a lot less than many growers think.

As a general guide, if you are remixing your nutrients between 7 and 10 days, then just topping off your reservoir with plain water will be sufficient. However, you will need to check daily because the strength of your nutrient will change as plants take up water.

The nutrient levels should sit in a range of between 800 to 1500 ppm (parts per million), this can vary depending on the kind of plants being grown.

Here we will look more in depth at how you need to set your reservoir and maintain the right levels of fertilizer and nutrients. We will also look at two ways growers determine the right times to add more fertilizer to their system.

Selection and Preparation of Nutrient Solutions

When it comes to hydroponic nutrients, you can go about this a few different ways. You can purchase ready-made solutions, you can buy nutrient solutions which come in two or three parts or you can make your own from scratch.

For growers with small gardens, it is advisable to go with the two- or three-part solution. This allows you to be flexible and tailor your nutrients to the type of plants you are growing, and the stage that they are at in their growth.

There are a few factors, which determine the proportion of nutrients you use in your system. This will be the same regardless of the way you get your nutrients from the above three methods.

  • Plant type and variety
  • Growth stage of plants
  • Plants parts you want to encourage growth and development
  • Intensity of light, weather, season and grow room temperatures
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If you decide to go with a ready-made solution, be sure it is made specifically for hydroponic systems. Fertilizers, which are developed for soil lack many of the micronutrients required as these, are already found in the earth.

How EC Levels Affect Hydroponic Nutrient Solutions

To determine the nutrient concentrations in your solution, you will measure the EC (Electrical Conductivity) – we’ve written a complete guide which you can find here. To do this, you will use a digital EC meter. Once you take a reading, this will be converted into the dissolved solids, or as we know them the PPM (Parts Per Million).

These EC meters can help when you are mixing your solution, and it is at the correct solution, and they can help monitor the concentration over time.

One thing to note is that EC levels will never weaken on their own, and will always become stronger as plants absorb water faster than they absorb nutrients.

These EC meters are vital and will help growers to prepare their solutions, monitor their concentrations, dilute these as necessary and know when it is nearly time to fertilize their system again.

EC Reading Problems

As helpful as EC meters are, they are not the solution to everything. While they are capable of giving you the PPM of your solution, they cannot differentiate between the various compounds of your nutrients. This can be a problem if you live in a hard water area, and a fair percentage of your PPM comes from unknown dissolved solids in your water.

Hydroponic Nutrient pH Levels

Once you have your initial mix, it will have a specific pH level. Depending on plant types, the optimal levels are around 5.5 to 6.3 in hydroponic systems. Each type of nutrient will be absorbed by your plants at varying rates, depending on the pH levels of your solution.

Solutions, which have a drop of under 5.5 of their pH, run the risk of having deficiencies in some nutrients while others are having a toxic effect as they are being absorbed too quickly.

If the pH rises too much, this can lead to speedier evaporation of micronutrients from the solution. This will lead to deficiencies in certain nutrients.

Checking pH levels is required almost daily, and sometimes, more than once per day. As plants continually absorb minerals and nutrients, pH levels will change, as will the overall EC / PPM of the solution.

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We’ve written complete guides to testing your pH levels, and showing how to balance your pH if it’s not quite right!

Topping Off and Adding Fertilizers

This is two parts of the same area in your system. With the above, we saw ways for a grower to understand what is happening with their nutrient levels inside their tanks.

It is from here that you can find when to add, or how often you should fertilize your hydroponic plants.

Once you run your system, test your levels and once everything stabilizes, you will see that your water levels drop as your plants absorb fluids and nutrients. Aside from this, there will be a loss of water through evaporation.

When you first fill your tank, you should mark the high water level. You should check water levels daily and only top up to this mark. Depending on the type of system you have, you will top off every few days. It is here that plant type and temperatures come into play.

As you add water to your tank, you should record how much you add, it is this that can help you determine when you need to flush your system.

As you progress with your system, you will come to find that no nutrient mix is perfect, and there will be problems along the way. For this reason, flushing a system is vital to have a fresh start and correct any imbalance in your system. pH swings or EC levels that are totally out of balance being the main things.

This flushing of systems comes under much debate and discussion. You will also find that this determines how often you fertilize your hydroponic system.

Adding Fertilizer after Flushing Systems

There are two ways that growers look at when to flush their system and thus introduce a new set of fertilizer to their system. A general rule, which is often used, is that reservoirs will be emptied and re-filled no longer, than ten days into any growing phase.

This will be the extreme case because it will be determined by EC levels. On average, the time to change would be between 5 and 7 days. However, these EC readings can cause the issues. Because they give an overall picture, it is hard to know which nutrients are at what levels.

Growers who follow these methods will do so because it is the only sure way of knowing what levels of each nutrient they have in their system.

The second method of adding fertilizer to your system goes a little further than the above. If you are rigid with a ten-day flush, then you can waste precious nutes.

The second way uses the 50% method. This looks very similar to the above yet it doesn’t have a set time associated with system flushing.

The way this works is to measure your reservoir when you first fill it, and record the number of gallons. Check your levels every couple of days and top up with plain water. You proceed in this manner until you have replaced 50% of your starting number of gallons.

Once you have replaced half the liquid, you then cease topping off your tank and let the solution levels run down until they reach the top of your water pump.

At this stage, you can clean and drain your tank, and then add a new batch of nutrients or fertilizer.

One tip when using this method is for flood and drain systems. Because there can be salt buildup, it is advisable to flush your growing pots, growing medium and also your plants to rid them of accumulated salts.


As you can see from the information above, you will in act fact only fertilize your system once at each stage of growth. This, of course, will vary depending how long it takes your plants to grow from seedlings until harvest.

Both of the methods above may be suitable for many growers, however, the 50% method will cut down on waste. However, as the nutrient solution will be weakened by half, you may begin to see slow-growing plants showing signs of nutrient deficiencies toward the time you are almost ready to flush your system, and add a new batch.

Finding the method, which is best for your garden, is straightforward, and monitoring pH and EC levels can be the easiest ways to make sure you have this control. One final note is that you are better to add less rather than more when it comes to hydroponic nutrients.

Related Questions

Why should I not add more nutrients when I top my system up with water? The reason for not adding more nutrients when you top up with water is that the concentration becomes stronger. When this happens, certain compounds become toxic to plants.

How does weather affect nutrient requirements? Plants will have higher nutrient requirements in the colder times of the year; they will also have a lower requirement in the hotter months when they need to take up more water. However, if your grow room is always the same temperature, or never falls below a set temperature, then this scenario should never occur.

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