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About This Item

Details

  • Measures some of the most important levels, including pH, ammonia, nitrite and phosphate to maintain ideal water condition
  • Comes with 6 bottles of test solutions, several laminated color-matching charts, 4 glass test tubes with snap-tight caps, a holding tray and an instruction booklet.
  • Comes with over 500 tests, so you can maintain the quality of your water.
  • The kit is both compact and convenient for easy storage.
  • Helps keep your pond water in tip-top condition for your finned friends.

Instructions

FAQ

Learn More About API From Our Team of Experts

About API Testing

Testing the Waters

For fish to thrive, their aquarium water must be similar to the water in their natural environment. Poor water quality can cause stress, illness and even the loss of your fish. Important water quality parameters include ammonia, nitrite, nitrate, and pH. These can vary over time, and they are invisible to the eye, which is why it is necessary to test weekly. Choose from a wide range of API testing options like the Freshwater Master Test Kit or 5-in-1 Test Strips to accurately evaluate your water.

Pressed for Time? Just Dip and Read

Simply dip an API test strip into your aquarium, swirl it twice, and then use the color-coded chart to determine if your water is within safe parameters or if adjustments are needed. That’s it! API test strips are available in a 5-in-1 version, which includes testing for pH, nitrite, nitrate, carbonate, and general hardness. Ammonia and pH test strips are also available so you can mix and match according to your needs.

The Scientific Approach

Get professional results from the comfort of your home with API test kits. Measure up to six parameters with API Master Test Kits, or pick and choose from a wide variety of individual test kits. Both types of kits come with test tubes and a laminated, calibrated color card. API test kits allow for numerous tests, making them an inexpensive way to help keep your aquarium water quality in check.

How to Correct Aquarium Water Parameters

Too Much Ammonia?

Ammonia is released into the water through gills, urine, uneaten food and more. API Ammo-Lock detoxifies it instantly.

Inappropriate pH Levels?

Fish require a specific pH level to thrive. Use API pH Down to lower freshwater aquarium water pH to the right level.

Too Much Nitrite?

Use API Quick Start to quickly consume nitrite and help maintain an active biological filter.

Nitrates Too High?

API Nitra-Zorb helps remove nitrate and other toxins that can be harmful to fish and lead to algae growth.

About API

The team at API has a passion for fish and understands the rewards and relaxation fishkeeping can bring. For almost 60 years, they have developed premium products with a focus on proven and effective results. API offers a range of testing kits, water conditioners and nutritionally superior fish foods. They are dedicated to making a better underwater world for the benefit of fish and those who keep them.

Shop API

Questions & Answers

4 Customer Questions


Will this testing kit help to identify indicators for blue-green algae with potential toxic cyanobacteria?

Answer by ChewyJun 22, 2019
This complete kit measures pH, ammonia, nitrite and phosphate levels to help maintain ideal water condition for your finned friends.

I have the kit with the 6 bottle to test the pond water. I have lost the instruction on how to mix can you help

Answer by ChewyJun 25, 2021
A digital copy of the instruction manual can be downloaded directly from the "Instructions" tab on our site.. The "Instructions" tab is located next to the "Description" tab under the product photos.

Is there a large difference between the pond test kit and the aquarium test kit? I have a pond and was wondering if it could be used for my aquarium as well.

Answer by ChewyMay 10, 2021
There are different tests between the kits. However, you may use either kit for either application. Both kits are meant to be used with freshwater.

does it have the items included to FIX any issues the test may find?

Answer by ChewyOct 17, 2020
The test kit doesn't include the products needed to resolve water concerns found by the tests.
4.7
Rated 4.7 out of 5 stars
35 Ratings

20 Customer Reviews



Rated 5 out of 5 stars
By Chad on Aug 11, 2025

Easy use

The kit is in a nice reusable container with everything you need to test the water. Simple instructions and solutions..

The kit is in a nice reusable container with everything you need to test the water. Simple instructions and solutions..


Rated 5 out of 5 stars
By Ruth on Jun 10, 2025

Effective Water Testing

It's a great tool to keep my fish pond in great shape. Now I know what chemicals to treat the water.

It's a great tool to keep my fish pond in great shape. Now I know what chemicals to treat the water.


Rated 5 out of 5 stars
By Heidi on Sep 24, 2024

Pond test kit

It’s so easy finding what I need on Chewy’s website.

It’s so easy finding what I need on Chewy’s website.


Rated 5 out of 5 stars
By Michael on May 26, 2024

Lightning Fadt

Orders with Chevy are always processed fast and they deliver first quality products that are packaged well. Thank you

Orders with Chevy are always processed fast and they deliver first quality products that are packaged well. Thank you


Rated 5 out of 5 stars
By Stephene on Aug 7, 2024

Test kit

Told us what was wrong so our stop dieing

Told us what was wrong so our stop dieing


Rated 3 out of 5 stars
By Emilee on Jul 16, 2022

Good kit, arrived broken

This is a good kit, but when I received it one of the tubes were broken and the box was cracked. I probably wouldn't order this in particular from Chewy because

This is a good kit, but when I received it one of the tubes were broken and the box was cracked. I probably wouldn't order this in particular from Chewy because of that.


Rated 5 out of 5 stars
By Julie on Oct 26, 2021

Fast and Effective

Easy to use and comprehensive testing kit. Very pleased.

Easy to use and comprehensive testing kit. Very pleased.


Rated 5 out of 5 stars
By Samantha on Aug 7, 2021

Worth it i will buy it again

So much more accurate than the strips might not be as easy as sticking a tab in the water but will save money from buying stuff to get your pond right. Tabs are

So much more accurate than the strips might not be as easy as sticking a tab in the water but will save money from buying stuff to get your pond right. Tabs are not as accurate. Love this and will buy it again.


Rated 5 out of 5 stars
By Guy on Jul 30, 2021

Easy to use test kit

Very easy to use, clear instructions. The different tests help give us peace of mind about our pond and our fish. Very happy with our purchase

Very easy to use, clear instructions. The different tests help give us peace of mind about our pond and our fish. Very happy with our purchase


Rated 5 out of 5 stars
By Blue on May 20, 2021

Help water kit

This is a great kit. Easy to use and you can check your pond water for slot of different issues and then correct it. Thank you.

This is a great kit. Easy to use and you can check your pond water for slot of different issues and then correct it. Thank you.