The Best pH Meter for Aquarium In 2022 | Buying Guide and Reviews

Larry Mills
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With pH levels being so important, it is important to know how to test this parameter in an aquarium.

PH is a measurement of how acidic or basic water is. It is an important factor in a healthy aquarium because it directly affects the normal behavior of the water and even the survival of your aquarium inhabitants.

Measuring the pH level in your aquarium with a pH meter is the best way to ensure that it stays at a healthy level. You have to keep your pH level between 7.0 – 8.6, although on the lower range of that scale is desirable.

The wrong pH level can lead to a number of issues like algae blooms, putting stress on the fish, and even death.

The most important thing you have to remember with using a pH meter is that there is no “one best pH meter” that works for every aquarium. Picking the right one for your aquarium environment is a process that’s going to involve some research.

We decided to write this post to tell you what things you have to consider when buying a pH meter to use for your aquarium, and also to recommend our favorite pH meters for use in an aquarium.

Apera Instruments AI209 Value Series PH20 Waterproof pH Tester KitBest OverallApera Instruments AI209 Value Series PH20 Waterproof pH Tester Kit

1. Apera Instruments AI209 Value Series PH20 Waterproof pH Tester Kit

Our rating: 9 / 10

Apera Instruments AI209 Value Series PH20 Waterproof pH Tester Kit

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10 – 200°F, Auto Temperature Compensation (ATC).

±0.1 pH Accuracy at 25°C (77°F)

Stainless Steel Probe, Safety Red Tip.

Frequently Asked Questions (FAQ)

What is the best pH meter to buy?

There are many different types of aquarium pH meter on the market right now. Each one has its own strengths. Some of them are very simple and inexpensive but not very accurate for measuring the pH levels in the aquarium. Some of them are much more expensive than others due to the extra features, which can be useful but not necessary.

One of the most vital aspects of maintaining the health of your fish is the pH levels. The pH levels of the water determines if your fish are going to survive or not. If the pH is too low, it can kill your fish. But, if the levels are too high, it can also kill your fish.

What is the most accurate way to test pH?

Always use independent, outside verification of pH measurements whenever possible.

If you already have a meter and are just looking at buying a new probe, all we can say is good luck. Different brands use different technologies, and even the methods used within different models of one brand can be very different. There are also differences in probe construction that can affect how a meter works and which probe you use, so don't assume that your pH meter is broken if the readings you get don't jive with the literature you find.

Why is the pH meter most accurate?

It is extremely important to monitor the pH of your aquarium and make periodic changes as necessary. If you're not familiar with how to test the pH of your aquarium, there are two main types of ways to go about it:

Use indicator strips – The strips react to the acidity of the water.

Use a pH meter – The pH meter measures the electrical resistance of the water.

Both operate quite simply.

The indicator strips are often coated with a chemical that is sensitive to the pH of water. As the water gets more and more acidic, the chemical changes color to reflect this change.

The pH meter is much more technical. The electrical current inside the water is measured and the reading is turned into a pH reading. This is a little more stable than the indicator strip and therefore more reliable.

How accurate are pH meters?

Ultimately, as with all other types of meters, how accurate is a pH meter depends on how well it has been calibrated. Most pH meters come with calibration solutions. Usually, the calibration process is done at the factory. If you have concerns that your pH meter is not accurate, ask your company for information on its calibration process. Most manufacturers offer a guarantee on their meters.

If your pH meter is not calibrated correctly, it will mean that your readings are off by a certain amount. In this case, you need to find the error yourself and then recalibrate the device.

Like all measurements, pH measurements will only be as accurate as the tools you use to make them. In the case of a pH meter, the accuracy of the pH reading is dependent on a number of factors including the type of pH electrode, the calibration process, and how you are using your pH meter.


If you want to take a more serious approach to monitoring your aquarium, a pH meter will be the best choice for you. A pH meter will let you know whether your tank has one of the two extremes or if it is in the optimal range (normally between 6.5 and 8.3). The pH meter is used by keeping it in the water while you test it. You need to buy 2 different kits for measuring pH level: the reagent and the electrode, which will be sold together. The electrode contains an ion-accuracy strip which is placed in a solution of water for accurate reading.

Our Recommendation

Apera Instruments AI209 Value Series PH20 Waterproof pH Tester KitBest OverallApera Instruments AI209 Value Series PH20 Waterproof pH Tester Kit