What are the Best pH Meters in 2023? [Ultimate Guide]

Unlike soil-based growing, hydroponic gardeners keep close control on every detail. Therefore, it’s crucial to monitor water quality, particularly the pH level of your fertilizer solution.

Many hydroponic components can be expensive; however, there are often significantly cheaper alternatives. As a result, many gardeners look for ways to save money and ask many questions.

Are cheap PH pens any good?

They’re also known as pH meters or pH testers, besides being nicknamed “pH pens.” You’ll find an ‘electrode,’ which all pH pens use to perform the same function as pH strips or drops. As a result, even a cheap pH pen will offer more precision.

There are high-priced and low-priced models available, and more affordable pH pens can be a viable choice for beginners. One downside is they may not last like more expensive variants. All pH pens, however, require frequent maintenance and calibration.

Best Overall
Bluelab pH Pen Pocket Tester
  • Easy to operate
  • Completely waterproof
  • Sponge in the cap keeps probe moist
Best Price
Dr. Meter Digital pH Meter
  • High Accuracy pH Tester
  • Backlit Two-Color LCD Display and ATC
  • 0-14pH Measurement Range
Best Small Kit
Apera SX620 pH Pen Tester Kit
  • The smallest pH pen
  • Pen Tester Kit with 0.01 pH Accuracy
  • Automatic 3-point calibration

Why Monitoring Hydroponic pH is Important

So, what is the significance of pH measurement? The pH of any growing medium, whether hydroponics or soil pH, influences plant growth.

It determines all nutrients available to plants and is more than just that some plants prefer acidic soils while others prefer more alkaline soils.

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You can devote a significant amount of time to ensuring that your plants receive all the nutrients they require. However, if your pH is off, this will affect your plants as they won’t take nutrients until the solution is in the proper pH range, which means you’ve squandered time and effort providing them to your system.

Most plants like a pH range of 5.5 to 6.5. While different plants have different requirements, a good rule of thumb is to stay within the optimal range of approximately 6.2.

Another advantage of keeping slightly acidic solutions in your hydroponic system is that waterborne algae do not thrive as well in an acidic environment.

How Does a pH Pen Work?

Now that we’ve established that pH accuracy and monitoring is critical to the growth of your hydroponic garden, it’s good to look at how these pH pens operate.

The hydrogen-ion concentration in your water is measured by your pH meter. It does so by measuring the difference in electrical potential between a reference electrode and a test electrode. So it is with this; the meter can tell if the solution is acidic or alkaline.

The pH pen features a glass electrode sensitive to hydrogen ions and a reliable reference electrode to simplify this operation. The difference between the two shows the pH of the liquid to the pH meter, and thus, you can adjust your nutrient solution as needed.

9 Top pH Pen Reviews

#1  Bluelab pH Pen
Best Overall

#1 Bluelab pH Pen

  • Dimensions:  4.32 oz, 8 x 2.3 x 0.9 inches
  • Calibration: 2 point calibration, 4.0 and 7.0 calibration solutions included
  • Storage Solution Included: no
  • Replaceable Probe: no
  • Waterproof:  yes
  • Battery:  1x AAA battery

The Bluelab pH pen is the best hydroponic pH meter available. It is pocket-sized for ease of carrying and storage, 100% waterproof, and measures pH and water temperature. In addition, the backlit LCD makes it easy to read results.

  • Easily measure pH and temperature with one pH reading
  • Completely waterproof
  • Sponge in the cap to keep the probe moist
  • A one-year limited warranty
  • Comes without a calibration kit
  • Sensor bulbs can be fragile
#2  Dr. Meter Digital pH Meter
Great Price

#2 Dr. Meter Digital pH Meter

  • Dimensions: 8.78 oz., 8.9 x 3.86 x 2.24 inches
  • Calibration: 3 point calibration, includes 4.0, 6.86, and 9.18 calibration solution,
  • Storage solution included:  yes
  • Replaceable Probe: no
  • Waterproof: yes
  • Battery: 2x AAA batteries

Dr. Meter pH meter tests both temperature and pH levels without breaking the bank. While not as elaborate or feature-rich as some of the other meters, the Dr. Meter device is a reasonable option and functions well.

  • Great budget choice for pH measurement
  • Easy calibration
  • It offers a large LCD screen, which is easy to read
  • Auto calibration with included solutions
  • Batteries are difficult to install
  • No replacement probes available
#3  Apera Instruments SX620 pH Pen/Tester Kit
Good Value

#3 Apera Instruments SX620 pH Pen/Tester Kit

  • Dimensions: 6 x 1 x 1 inches; 5 oz.
  • Calibration: 3 point calibration, 4.0, 7.0, and 10.0 calibration solutions included
  • Storage solution included:  yes
  • Replaceable Probe: yes
  • Waterproof: yes
  • Battery: 2x CR2032 Lithium ion batteries

The narrow probe on this Apera Instruments pen tester quickly tests the pH level in everything from test tubes to big reservoirs. This device, like the other Apera Instruments devices, comes as a complete kit and needs calibrating regularly. Overall, it’s a great, tiny device for keeping track of your solution, and the entire testing and calibration kit is pocket-sized.

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  • Slim, easy to replace probe
  • Comes with calibration solutions, carrying case, and storage solution
  • Long battery life
  • Thoroughly dust and waterproof and will float
  • The small LCD screen is difficult to read
  • It takes longer to conduct pH tests
#4  APERA INSTRUMENTS AI209 Value Series pH Test Kit
Great Value

#4 APERA INSTRUMENTS AI209 Value Series pH Test Kit

  • Dimensions: 77.01 x 1.61 x 1.18 inches; 3.9 oz.
  • Calibration: 2 point calibration, 4.0 and 7.0 calibration solutions included
  • Storage Solution Included: no
  • Replaceable Probe: no
  • Waterproof: no, water resistant
  • Battery: 4x AAA batteries

Apera Instruments’ value-level offering is also from the same stable. The AI209 is their low-cost test kit, and it’s popular. This water pH tester is portable and straightforward to use. The kit includes all the calibration solutions you’ll need to get accurate results. You can’t go wrong with the Apera Instruments AI209 if you want something cheap but all-inclusive.

  • Easy to calibrate
  • Long AAA battery life
  • Comes with a probe cleaning brush & calibration solution
  • Thoroughly water and dustproof
  • The probe sensor can get bubbles
  • It takes longer to take readings
#5  Apera Instruments AI311 Premium pH Test Kit
Great Pocket Kit

#5 Apera Instruments AI311 Premium pH Test Kit

  • Dimensions: 7 x 1.6 x 1.6 inches; 4.7 oz
  • Calibration: 3 point calibration, 4.0, 7.0, and 10.0 calibration solutions included
  • Storage Solution Included: yes
  • Replaceable Probe: yes
  • Waterproof: yes
  • Battery: 4x AAA batteries

This accurate pH meter is an excellent choice. Apera Instruments offers a variety of versions, and this one sits at the top end. It is sold as a complete kit that includes calibration solutions, a high-quality glass probe, and even storage and battery options.

  • Easy to calibrate
  • The probe is replaceable
  • 3-color LED window identifies operation mode
  • Fully waterproof
  • Needs protection from frigid conditions
  • Replacement probes are expensive
#6  Oakton EcoTestr Pocket pH Meter

#6 Oakton EcoTestr Pocket pH Meter

  • Dimensions: 8.6 x 5 x 1.4 inches; 5.6 oz
  • Calibration: 3 point calibration, calibration solutions not included
  • Storage Solution Included: no
  • Waterproof: yes
  • Battery: 4 A76 1.5V miniature alkaline batteries

The Oakton EcoTestr is an old standard for a pocket-sized digital pH tester. It offers a larger display battery life indicator, and the cap can be fixed to the other end of the pen while you use it.

  • A reliable option for precise results
  • Measures pH and temperature
  • Fully Waterproof and dustproof
  • Pocket size for convenience
  • 1-year limited warranty
  • It might not last as long as some other offerings
  • It requires frequent calibration
#7  Bluelab Guardian pH/Conductivity Monitor
Best Combo Meter

#7 Bluelab Guardian pH/Conductivity Monitor

  • Dimensions: 7.5 x 5 x 1.5 inches, 8 oz.
  • Calibration: 2 point calibration, 4.0 and 7.0 pH solutions included
  • Storage Solution Included:  no
  • Replaceable Probe:  yes
  • Waterproof:  no, water resistant
  • Battery: 2x AAA batteries

The Bluelab Guardian Monitor is a fabulous combo meter. This meter is more expensive than the others, but it is perfect for serious growers with the budget for it. Because it is always on and monitoring your garden, you will be notified when your metrics get out of range. This is one of the best pH meters out there and well worth the expense.

  • Large LCD display
  • Continuous monitoring
  • Flashing alarms alerts when outside ranges you set
  • Also monitors conductivity (EC, TDS, ppm 500, ppm 700 and CF)
  • Expensive
  • Probes can wear quickly and need replacing every 3 or 4 months
#8  Bluelab Combo pH Meter
Best Value Combo Meter

#8 Bluelab Combo pH Meter

  • Dimensions: 6.1 x 3.1 x 1.5 inches; 5.3 oz.
  • Calibration: 2 point calibration, 4.0 and 7.0 pH solutions included
  • Storage Solution Included:  no
  • Replaceable Probe: yes
  • Waterproof: no, water resistant
  • Battery: 2x AAA batteries

The Bluelab Combo Meter is the industry standard for pH, temperature, and PPM/EC/TDS meters. 

  • Measures pH, temperature meter, and electro conductivity (EC)
  • It comes with a double junction pH probe that is replaceable
  • Comes with an auto-off function
  • Auto calibration
  • Probes are fragile
  • Units aren’t waterproof while the probes are
#9  Hanna Instruments 9813-6N pH/EC/TDS Meter
Best Quality

#9 Hanna Instruments 9813-6N pH/EC/TDS Meter

  • Dimensions: 5.7 x 3.1 x 1.5 inches, 8.1 oz. 
  • Calibration: 1 point calibration, 7.0  solution included
  • Storage Solution Included: no
  • Replaceable Probe: yes
  • Waterproof: yes
  • Battery: 1x 9V battery

Hanna is another well-known manufacturer of pH and combo meters. The built-in automatic calibration reminder is one of the best features of this pH meter. You won’t forget to calibrate and wonder why your readings are wrong. However, you pay for this feature.

  • Measures pH, temperature, electro conductivity (EC), and total dissolved solids (TDS), all in one meter
  • Great LCD display that is backlit simple to read
  • Testing and calibration are simple to perform
  • Waterproof
  • The cap comes without a seal lock
  • Doesn't include storage solution

Manual pH Testing vs. Digital pH Meters

There are two basic types of pH testing: manual and digital. If you are a serious hydroponic grower, you already use a digital pH meter or looking for a good pH pen.

Here you can find a breakdown of the things you need to know about manual testing against digital pH testing.

Manual pH testing

Manual pH testing is performed with a basic kit, like the water pH test kit used to evaluate the pH of a swimming pool. Manual water pH test kits are less expensive than digital pH meters and are much easier to use.

You have less worry about falling and breaking the meter, or parts from the kit corroding and stop working. These can make manual testing kits suitable for growers who are just starting in hydroponics and need a cost-effective way of monitoring their nutrients.

Downsides to Manual pH Testing​

Manual pH testing has drawbacks that make it unsuitable for some. Working with manual pH test strips or pH fluid takes more time and effort.

Time management can be an issue for dedicated growers, making manual methods of testing unfeasible.

Accuracy is another issue as pH strips can be hard to read or translate the results, particularly when colorblind. Inaccurate reading can influence your system. Even with good eyesight, it’s challenging to decipher the colors against the table to determine what the reading is supposed to be.

Digital pH Testing

If you intend to perform lots of hydroponic cultivation, digital pH meters are the way to go. These versatile meters can last for ages when cared for and calibrated correctly. In addition, they are more accurate than manual pH testing methods.

Digital meters are also fast, allowing you to test frequently and quickly, making them significantly more efficient than manual pH meters.

Downsides to Digital pH Meters​

Of course, all this comfort and efficiency comes with a price tag. The top digital pH meters can be expensive.

They also require more care and need calibration. Digital pH meters must be calibrated regularly to remain accurate, and without proper maintenance, your expensive digital pH meter will fail.

Caring for Your pH Meter

All your calibration efforts will be wasted if you don’t take the time to care for your pH meter.

Even if most instructions are lengthy, the first thing you should do when you receive a new pH meter is read the relevant handbook that comes with it. The instructions should include how to care for your pH meter. If they don’t, contact the manufacturer to find out why.

You must complete the following with every pH meter:

  • Pay attention to the detailed instructions
  • Maintain calibration
  • For best saturation, keep meters with storage solutions in the cap upright
  • To remove air bubbles, lightly swirl your meter in the storage solution
  • Don’t touch the sensor electrode or reference cell, as oils on your skin can damage the sensor and influence accurate readings
  • Keep away from excessive temperatures and humidity
  • Do not store your sensor in distilled water
  • Handle with caution

How do you calibrate a pH meter?

If you’re using the digital path as most gardeners end up doing, you’ll need to know the correct pH pen calibration steps.

You’ll need a buffer solution before you start. A buffer solution is a pH meter standard reference point that a laboratory has validated. Most buffer solutions are liquid, but they can also be purchased in powder form and mixed with water if desired.

Once you have your buffer solution, follow these steps to calibrate your pH meter:

  1. To get accurate readings, immerse your meter in the buffer solution
  2. Adjust your meter reading to match the buffer solution according to the manufacturer’s instructions (these can differ for digital and analog meters
  3. Repeat in a different pH buffer solution for high accuracy
  4. Calibrate your pH meter once a week or at least once a month if you use it frequently
  5. When replacing a sensor, always calibrate your pH meter to ensure accurate readings
  6. Instructions will be sent with your pH meter. If the instructions differ, make sure you read them before calibrating your meter


You can spend any amount of money on pH pens, and although you may think more expensive options offer better results, you can still get poor results if they are not calibrated correctly.

Every option here is suitable for all gardeners and covers all system sizes from the smallest to the largest.

No matter which you go for, you will quickly be able to offer your plants the ideal pH within a shorter time than using older methods.

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