Best Aquarium Water Test Kits (Reviewed 2021)

Updated on January 13, 2021 by

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What are the aquarium water test kits for?

A successful aquarium comes with lots of accessories. To name a few, we can definitely mention: a heater to warm up the water and keep it at constant temperature levels, a HOB filter or a canister filter to clean the water of any harmful debris, a LED lighting system to facilitate plants or coral growth, but still, with all this equipment it is important to check the aquarium water regularly using the best aquarium water test kits.

The water test kits help you maintain the aquarium water at the optimal parameters, regardless of whether it’s a freshwater or a reef tank. It’s really not important what kind of setup you have, what’s crucial though is to make sure your aquarium is thriving.

Best Aquarium Water Test Kits Compared

ImageProductFeaturesCheck Price
Best for Freshwater
API FRESHWATER MASTER TEST KIT 800
API FRESHWATER MASTER TEST KIT 800

Environment: Freshwater only
Checks for: pH, Ammonia, Nitrite, Nitrate
Tests: 800

Check On AmazonCheck MarineDepot
Best for Saltwater
Red Sea Fish Marine Care Test Kit
Red Sea Fish Marine Care Test Kit

Environment: Saltwater only
Checks for: nitrate, nitrite, ammonia, pH, alkalinity
Ammonia tests: 100
Nitrate tests: 100
Nitrate tests: 60
pH tests: 100
Alkalinity tests: 55

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Good All-round
API SALTWATER MASTER TEST KIT 550
API SALTWATER MASTER TEST KIT 550

Environment: Saltwater only
Checks for: pH, Ammonia, Nitrite, Nitrate
Tests: 550

Check On AmazonCheck MarineDepot
Fast Ammonia Tests
API AMMONIA 130
API AMMONIA 130

Environment: Freshwater and Saltwater
Checks for: Ammonia
Tests: 130

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Great for Reef
API REEF MASTER TEST KIT Reef
API REEF MASTER TEST KIT Reef

Environment: Saltwater
Checks for: CA, carbonate, hardness and phosphate
Tests: 7 test bottles

Check On AmazonCheck MarineDepot
Complete Tests
Tetra Complete Kit 6 in 1 Strips
Tetra Complete Kit 6 in 1 Strips

Environment: Freshwater & Saltwater
Checks for: ammonia, nitrates, nitrites, hardness
Tests: 25

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Good Deal
Aquarium Test Strips 9 in 1
Aquarium Test Strips 9 in 1

Environment: Freshwater & Saltwater
Checks for: hardness, chlorine, iron, copper, nitrite, nitrate, pH, total alkalinity & KH / carbonate
Tests: 150

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Good Deal
Capetsma 9 in 1 Aquarium Test Strips
Capetsma 9 in 1 Aquarium Test Strips

Environment: Freshwater & Saltwater
Checks for: pH, Nitrate, Nitrite, Carbonate, TDS, Chlorine, Alkalinity, Iron, Copper
Tests: 50

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Beginner’s Set
API 5 in 1 Test Strips Freshwater & Saltwater
API 5 in 1 Test Strips Freshwater & Saltwater

Environment: Freshwater & Saltwater
Checks for: pH, Nitrite, Nitrate, Carbonate, Hardness
Tests: 25

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Cheap Test Strips
Lifegard Aquatics 5 Way Test Strip
Lifegard Aquatics 5 Way Test Strip

Environment: Freshwater & Saltwater
Checks for: alkalinity, pH, nitrite, nitrate, hardness
Tests: 25

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What shall we test for in aquarium water?

Depending on whether you have a freshwater or a saltwater setup, different parameters should be monitored. What’s important here is that you have to make sure you’re using the suitable water test kit for the kind of water your aquarium has. Saltwater test kits won’t work with freshwater and the other way around, but we’ve got you covered on this.

Freshwater aquarium water testing

The main water parameter that every fishkeeper has to monitor constantly is the pH level. The water pH can range from acidic to alkaline values being measured from 0 to 14. Not having the right pH for the kept species, can be really stressful for the fish.

While plenty of aquarium species prefer a somewhat neutral pH ranging from 6.0 to 8.0, other species like Discus, Angelfish, or German Blue Rams prefer slightly acidic water.

Next to the pH, the other crucial parameters we should keep an eye on, are ammonia, nitrites, and nitrates. Too much ammonia, for instance, can be extremely harmful to aquarium fish, causing a great deal of damage, eventually killing the fish. In a healthy aquarium, the ammonia levels should always be zero.

The aquarium beneficial bacteria break down ammonia, and the nitrites are the result of this process. Nitrites are therefore not as harmful as ammonia, but they shouldn’t reach high levels. At the final stage of the nitrogen cycle are the nitrates. They aren’t harmful and they are a sign of a well-cycled tank.

The next thing to keep an eye on in our aquarium water is its hardness that comprises total dissolved materials in water, mainly calcium and magnesium.

For example, if you’re only interested in measuring the water TDS, you may take a look at our article on the best TDS meters for aquarium.

Some species particularly prefer water with higher levels of hardness. Such species are for example African Cichlids.

Saltwater aquarium water testing

In addition to the freshwater parameters, when testing aquarium saltwater, we should keep an eye on salinity. For the optimal saltwater tank parameters, you can take a look at our corresponding article here.

To efficiently keep an eye on salinity levels, you might be interested to check out our article on the best salinity refractometers.

In reef tanks, elements like phosphate, calcium, and magnesium should be also kept under the radar. They are important for healthy coral growth, but too much phosphate can stimulate algae growth.

The water for a saltwater aquarium needs to go through a RO/DI process before being used in the tank, and for that, we recommend using one of the best RO/DI water filtration systems, carefully selected in our article on the subject.

1. API Freshwater Master Test Kit – Best Freshwater Aquarium Test Kit

API FRESHWATER MASTER TEST KIT 800

It is designed specially for freshwater testing only and should be of great help, monitoring the tank’s water once a week.

The package includes 7 bottles of testing solutions, 1 color card and 4 glass tubes with cap that will help you to accurately monitor 5 most vital water parameters levels in freshwater aquariums: pH, high range pH, ammonia, nitrite, nitrate.

We recommend this as a great deal for the price as you get 800 freshwater tests that will last for quite a while.

PROs
  • #1 bestseller freshwater aquarium test kit
  • Clear instructions in multiple languages
  • Tests pH, high range pH, ammonia, nitrite, nitrate
  • Contains a total of 800 tests available
CONs
  • Only suitable for freshwater tanks

2. Red Sea Marine Water Test Kit – Best Saltwater Aquarium Test Kit

Red Sea Fish Pharm Marine Care

Manufactured by a well known brand – Red Sea, the marine care test kit includes all of the main kits you need to run a thriving saltwater tank.

Will allow you to easily monitor the nitrate, nitrite, ammonia, pH, alkalinity levels and its easy-to-use tests come with simple instructions and handy color charts.

The RedSea Marine water test kit includes 100 ammonia tests with an accuracy of 0.02 ppm, 100 and 60 nitrate tests with an accuracy of 2 ppm and 0.05 ppm that will provide accurate readings, mandatory when we talk about reef water test kits.

The pack has as well 100 pH tests with an accuracy of 0.2 ppm and 55 alkalinity tests with an accuracy of 1 dKH/0.36 meq/L.

PROs
  • Great professional saltwater testing kit
  • Tests nitrate, nitrate, ammonia, pH and alkalinity levels
  • 100 Ammonia tests with accuracy of 0.02 ppm
  • 100 pH tests with accuracy of 0.2 ppm
  • 55 alkalinity tests with accuracy of 1 dKH/0. 36 meq/L
CONs
  • Only for saltwater testing

3. API Saltwater Master Test Kit

API SALTWATER MASTER TEST KIT 550

The pack includes 550 saltwater test kits accompanied by 6 bottles of testing solution, 1 color card and 4 glass test tubes with cap.

Keeping an eye on the levels of high range pH, ammonia, nitrite and nitrate has never been easier. The saltwater API master kit will help you monitor and adjust pH too and prevent invisible water problems that can be very harmful to fish.

Provides very accurate test results that ultimately prevent any fish stress or even loss. We recommend that you use the tests on a weekly basis, for effective monitoring, but also if any water or fish problems are spotted.

PROs
  • 550 tests available
  • Tests levels of high range pH, ammonia, nitrite and nitrate
  • Helps monitoring and adjusting pH levels
CONs
  • Only for saltwater

4. API Ammonia Water Test Kit – Freshwater & Saltwater Aquarium Water Test Kit

API AMMONIA 130 Test Freshwater & Saltwater

If you need to check for particular elements and parameters in your saltwater tank, then these packs are the best choice.

They aren’t all in one packs, but are sold separately as it follows: Ammonia, Calcium, Carbonate Hardness, Copper, GH & KH, High range pH, Nitrate, Nitrite, Phosphate, pH and pH & Adjuster.

Looking at all these particular options, these water test kits are a great deal for both marine and freshwater setups. You can choose from a wide range of products suitable to test any water parameters in your saltwater tank.

PROs
  • Suitable for both freshwater and saltwater
  • 130 easy to use water test strips
  • Comprehensive instructions in multiple languages
CONs
  • To test all parameters means getting all the different test kits

5. API Reef Master – Best Reef Tank Water Test Kits

API REEF MASTER TEST KIT Reef Test Kit

Having the water parameters under control in a reef tank is an absolute must. The API reef master kit includes 7 bottles of testing solution, 2 helpful color cards, and 4 glass test tubes with caps.

With 500 tests available in the pack, you can easily measure levels of calcium, carbonate, water hardness and phosphate which are critical elements for the well being of corals in a reef tank.

It will surely help to prevent invisible water problems that can be harmful to marine fish and even cause fish loss. The tests are designed for regular checks in reef aquariums only and will be very efficient for weekly water parameters monitoring.

PROs
  • Tests calcium, carbonate, water hardness and phosphate
  • Easy to use and very accurate for reef tanks only
CONs
  • Many complaints about bottles leaking

6. Tetra EasyStrips 6 in 1 & 25 Ammonia Strips

Tetra EasyStrips Complete Kit 25

The nice catch with the Tetra aquarium water test kit is that it can be used for both freshwater and marine setups and it’s available with 25 water test strips.

With just one test strip, you can easily monitor ammonia, nitrates, nitrites, water hardness, chlorine, alkalinity, and even pH levels. When testing, just dip into the water, wait 60 seconds, and then simply read the results.

The water test strips be used on a weekly basis to monitor aquarium parameters after water changes or when adding new fish for instance.

PROs
  • Tests ammonia, nitrates, nitrites, water hardness, chlorine, alkalinity and pH levels
  • Suitable for freshwater and saltwater
CONs
  • Only 25 water test strips in a pack

7. JNW Direct 9 in 1 Aquarium Water Test Strips

Aquarium Test Strips for Fish Tank

With 150 water test strips available, perhaps the JNW Direct is the best overall aquarium water test kit.

It will check for 9 crucial aquarium parameters: total hardness, free chlorine, iron, copper, nitrite, nitrate, pH, total alkalinity & KH / carbonate.

It is very easy to check your aquarium water with this kit, and the reliable results are simple and very clear to interpret. Basically, you have to simply dip and compare with the large color chart on the bottle.

With the included bonus mobile app you can efficiently record, track, and monitor your aquarium water test results with great accuracy. The app is available on both platforms iOS and Android.

PROs
  • 150 test strips suitable for freshwater and saltwater
  • Tests 9 parameters: total GH, chlorine, iron, copper, nitrite, nitrate, pH, total alkalinity & KH, carbonate
  • Has a mobile app to easily keep a record of your tests
CONs
  • Does not test ammonia

8. Capetsma 9 in 1 Aquarium Water Test Strips

Capetsma 9 in 1 Aquarium Test Strips

Another great choice of a water test kit for your aquarium whether freshwater or saltwater setup.

With 50 water test strips, you can easily check the levels of pH, nitrate, nitrite, carbonate, general hardness (TDS), chlorine, total alkalinity, iron and copper.

The bottle has all the needed charts imprinted on it, so simply dip the test strip into the aquarium water and have the results checked against the bottle chart.

The water test kits should be kept in a dry place, perhaps in the aquarium stand, and kept away from light. The pack is valid for 24 months, so it’s important to check the validity date when making a purchase.

PROs
  • 9in1 complete water test kit
  • Suitable for freshwater and saltwater tanks
  • Monitors levels of pH, Nitrate, Nitrite, Carbonate, GH (TDS), Free Chlorine, Total Alkalinity, Iron, Copper
CONs
  • Does not test ammonia

9. API 5 in 1 Aquarium Water Test Strips for Freshwater & Saltwater

API 5-in-1 Test Strips Freshwater and Saltwater

A comfortable aquarium water test kit, that includes a total of 100 tests strips – in the biggest option. Should you need less tests strips, then also 4 and 25 options are available.

The test strips are suitable for both freshwater and saltwater regular tests. You will be able to easily check the water levels of pH, nitrite, nitrate carbonate and general water hardness.

To have the aquarium water tested, you just have to dip the test strip into water for about 30 seconds, and then compare the strip against the colors on the pack for quick and accurate results. It is ideal to have the aquarium water checked on a weekly basis, especially after water changes, or if new fish have been introduced and there can be some changes in the water parameters.

PROs
  • Tests pH, nitrite, nitrate carbonate and GH
  • Suitable for freshwater and saltwater tanks
  • 100 test strips available, but also 4 or 25
CONs
  • Does not check for ammonia levels

10. Lifegard Aquatics 5 Way Aquarium Water Test Strips

Lifegard Aquatics 5 Way Test Strip

This is a great water test kit, for regular quick checks during the week. In case something weird is noticed with the water parameters we recommend a second check with a more complex water test kit.

The pack includes a total of 25 test strips suitable to test water alkalinity, ph, nitrite, nitrate, and general hardness.

Can be used without any issues for saltwater or freshwater aquariums or even for ponds. The strips in the 5 in 1 kit are of course non-toxic, easy to use and provide quick and accurate results.

PROs
  • Tests alkalinity, ph, nitrite, nitrate, and hardness
  • Suitable for freshwater, saltwater tanks or even ponds
  • Easy to use, quick and results
  • Wide and clear display
CONs
  • Doesn’t test ammonia

Frequently asked questions

What is the best aquarium water test kit?

It really depends on the aquarium setup and what exactly do you want to test. a great overall aquarium water test kit is, for example, Tetra EasyStrips 6in1 Testing Strips and 25 Ammonia Testing Strips.

What should I test my aquarium water for?

The most important water parameters that should be regularly monitored are ammonia, nitrite, nitrate, pH, hardness, alkalinity, and possibly phosphate depending on the setup. Another important water parameter, however, is the water temperature, which could be critically important depending on the species kept in the tank.

How often should aquarium water be tested?

In a new aquarium, for instance, the water should be checked every 2-3 days. For a fully cycled tank, the checks can be less frequent, like weekly or even monthly is the tank is really running smoothly.

To conclude

To sum up, I think we all agree that there shouldn’t be any aquarium without a water test kit nearby.

It’s absolutely mandatory to monitor the water parameters especially if the tank is not yet cycled, or it’s overstocked or perhaps you’ve been gone for a few days and your neighbor might have overfed the fish and a water change is mandatory.

It’s therefore mandatory to keep an eye on the water parameters using the best aquarium water test kit to ensure our environments are operating smoothly and the fish are thriving. We hope we were of help here guiding you what’s the best test kit for your setup.
Before choosing one, keep in mind that some aquarium water test kits are only suitable for freshwater, while others only for saltwater.

There are also some kits that for instance don’t check the ammonia levels, which is definitely a critical element to keep an eye on. If you decide to get a water test kit that won’t check for ammonia levels, then perhaps it’s a good idea to get an internal ammonia checker like the Seachem Ammonia Alert, which will help you constantly monitor if there are any ammonia spikes.