I assume that you’re here because you want to learn more about pH water meters so you can purchase the best one! In this article, we will put in a quick review of the best options in the market so you won’t have to.

Best water pH meters

Apera Instruments AI209 Value Series PH20 Waterproof pH Tester

APERA INSTRUMENTS AI209 Value Series PH20 Waterproof pH Tester Kit, ±0.1 pH Accuracy
  • Easy auto. calibration with buffer recognition; auto. temp. compensation (ATC) ensures accuracy in various...
  • Backed by Apera quality pH sensor with low impedance, ensuring high response rate
  • Comes in a rugged carrying case with pH 4&7 buffers and a lanyard

This is quick, affordable, and of high quality. Its features allow for a reliable measurement taking of general water solutions like water treatments, pools, spas, horticulture, and others.


  • Switchable between standard pH series, USA or NIST
  • Adjustable reading between fahrenheit and celsius
  • Large and clear LCD screen display
  • Smiley face appears if reading is normal or stable
  • Durable
  • Water-resistant


  • The 10 testing solution needed to measure saltwater tanks is not included in the kit
  • Flimsy pocket clip


VIVOSUN pH and TDS Meter Combo

VIVOSUN pH and TDS Meter Combo, 0.05ph High Accuracy Pen Type pH Meter ± 2% Readout Accuracy 3-in-1 TDS EC Temperature Meter for Hydroponics, Household Drinking, and Aquarium, UL Certified
  • Application: Great for all home and laboratory TDS & pH testing applications including aquariums, swimming pools
  • PH Meter: Full measurement range of pH 0 - 14, reliable and quick readings
  • 3-in-1 TDS Meter: Measurement Range 0-9990ppm, 0-9990µs/cm; Accuracy ± 2%, 0.1- 80.0°C, 32.0-176.0°F; Note:...

his is a great pH water meter for aquariums and swimming pools. The reading goes from 0 to 14 which is a wider capability compared to others. On top of that, it will give you accurate readings quickly!


  • Lock function to ensure exclusion of other factors that may influence the reading
  • Portable
  • Ergonomic design


  • No calibration powder included
  • Pricey
  • Calibration changes from time to time so adjustments before using it should be done if needed

Apera Instruments AI311 Premium Series PH60 Waterproof pH Tester

Apera Instruments AI311 Premium Series PH60 Waterproof pH Pocket Tester Kit, Replaceable Probe, ±0.01 pH Accuracy
  • NOTE: A few drops of water are added to the electrode cap before the product leaves the factory. This is to...
  • Accuracy: 0.01 pH; range: -2.00 to 16.00 pH, 32 to 122˚F (0 to 50˚C); Auto. Power-Off: 8 minutes without...
  • Easy 1-3 points auto. calibration, recognizes 5 types of solutions (1.68, 4.00, 7.00, 10.01, 12.46); Auto Temp....

For more professional pH measurements, this one is a great option. It houses an accurate sensor that boasts of just ±0.01 pH margin of error with a -2.00 to 16.00 pH and 32 to 122 degrees fahrenheit range. All these without having to wait for so long. 

This product has an IP67 water-resistant rating with an exterior that’s rugged enough that it stays easy to handle in difficult conditions. The probe is replaceable so no need to worry if you happen to break it!


  • Large and easy-to-read LCD display
  • 3 backlit colors: blue for measurement, green for calibration, red for out-of-range readings
  • Kit comes with 4 AAA batteries
  • 2,000 runtime hours
  • Replaceable probe sensor


  • Replacements for calibration and storage solutions are pricey
  • Water-resistant meter but not submergible

Bluelab PENPH pH Pen Fully Waterproof Pocket Teaser

Bluelab PENPH pH Pen, Digital Meter for Water with Easy Two Point Calibration and Double Junction Probe Test Kit for Hydroponic System and Indoor Plant Grow, White
  • Measures pH in nutrient solution (acid or alkaline) for precise up and down adjustment with lab quality glass...
  • This hydroponics tester has ATC that provides consistent reading regardless of any fluctuations in temperature;...
  • Double junction electrode has a longer lifespan compared to standard probes due to less contamination and is more...

This is a fully waterproof pH water meter that can last for longer than other units. The device is sensitive and calibration easily goes wrong but nothing the care guide can’t help you with!


  • Great for everyday maintenance of gardens, pools, or aquariums
  • Simple user interface
  • Large and clear LCD display
  • Calibration will last for months
  • Re-calibration only takes about a couple of minutes
  • Reliable and high quality performance
  • Bluelab is a trusted hydroponic testing equipment brand!


  • Cap is difficult to take off once left sitting on the meter for more than a day
  • Sensor may be damaged if kept wet

HM Digital PH-200 Waterproof Temperature PH Meter

HM Digital PH-200 Waterproof Temperature PH Meter, 3.3" x 8.5" x 2", White
  • Measures pH and Temperature, Range: 0-14 pH, 0-80 °C, 32-176 °F
  • Autoranging three point calibration with digital fine tuning
  • Waterproof housing (IP-67 rating)

A more affordable yet reliable option is this one from HM Digital. It is slick and is insanely lightweight for the user’s comfort. It is water-resistant and fares well even in harsh conditions. On top of that, it can also measure temperature. A storage solution and a single-use pH 7.0 buffer pack come with the kit.


  • Large and easy-to-read screen
  • Automatic digital calibration button
  • Data-hold feature allows longer duration display of the last reading
  • Auto-off function


  • Requires storage in a buffer solution which evaporates and runs out quickly
  • Frequent calibration is required

Buyer’s guide

Ease of use

While most pH meters come with user manuals that are easy to learn, some are still more user friendly than others.


The goal is to find a pH meter that provides repeatable and consistent accurate results. A margin of error of ±0.01 to ±0.02 is promising. Besides, the goal is to get accurate results so it’s best to opt for devices that can offer that to you the most.

Versatility and functionality

Some models require calibration before first use but that’s relatively quick to do. There are devices that can measure temperature, electrical conductivity (EC), and total dispersed solids (TDS) on top of being able to measure pH level.


There are three types of pH testers: benchtop, portable handheld, and pen-style. Out of the three, the most precise is the benchtop but they are also pricier and less mobile.


To get accurate results, calibration is critical. Thus, it’s important that you know when to calibrate your device. If the accuracy of the measurement is vital for you, you may calibrate every before use. Besides, it only takes a few minutes. If for general usage at home, you may calibrate weekly instead. 

Temperature compensation

Temperature can affect your reading, so you should opt for devices with temperature compensation features to ensure that the different temperatures will have no effect on the measurement.

How to use a pH meter?

ph meter

A pH meter has two main components: the meter and the digital element. Electricity principles are used to test water samples, thus, an electrical circuit is created through a test solution. This is pretty easy to handle and while most pH meters function the same way, you can never go wrong with reading the user manual!

How is pH measured?

The device measures the concentration of hydrogen ions to determine the pH level. The more positively-charged hydrogen ions there are, the more acidic the solution is and vice versa. The pH level of pure water is 7. Anything lower is acidic and anything higher is basic. If you know how batteries work, this simply means that it’s producing more voltage. 

Calibrating is an important process because a pH tester works like a voltmeter. They measure the solution’s electrical potential and compare it to an already identified value. The difference between these two is used to calculate the difference in pH.

Care guide

Calibration is vital, but if you do not take care of your device properly, it can still retire earlier than expected. Consult the instruction manual for specific means to care for your device. Generally speaking, here are great things to do to maintain your pH meter well:

  • Read the instruction manual
  • Calibrate frequently
  • Handle with care
  • Never store the sensor in distilled  water
  • Don’t touch the sensor electrode or reference cell to keep the oil on your skin from being in contact with them as it can cause damages
  • Store properly with cap upright and with storage solutions
  • Get rid of air bubbles by lightly swirling the meter in storage solutions

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