Most water problems are invisible to the eye. Quickly measure and modify the six aquarium levels that are most important to the health of your freshwater fish with the API FRESHWATER MASTER TEST KIT. To stay healthy and thrive, fish need properly balanced levels of ammonia, pH, high range pH, nitrite and nitrate. These levels can change rapidly and create harmful conditions when fish waste, uneaten food or other organic matter accumulate, or when untreated water is added. If left uncorrected, all of these can be harmful or even fatal to fish, with consequences such as reduction of oxygen, increase in stress and higher risk of disease. The API FRESHWATER MASTER TEST KIT measures these six parameters with scientific accuracy and provides professional results. It comes with four glass test tubes, a holding tray, test tube rack and computer calibrated, laminated color card. Just fill the test tubes, add the test drops and compare results to the color card. Then follow the recommendations on the card if action is required. With API Aquarium products, it’s easy to keep a beautiful saltwater, freshwater or reef aquarium. For over 50 years, API has been creating innovative, research-driven solutions that make it easier to care for your fish and aquarium. API Aquarium Treatment Supplies are designed to work in conjunction with each other to provide best results to control algae, promote healthy bacterial growth and help control and cure fish diseases and conditions such as ich and fin rot. They work to provide a safe, hospitable environment for fish such as tropical community fish, cichlids, goldfish and more. With API, you can spend more time admiring your fish, and less time scrubbing your tank. Make sure to use all products as directed in order to ensure the best results.
From the manufacturer


Testing the Waters
In order for fish to thrive, water must be similar to that which could be found in their natural environment. Poor water quality can cause fish stress, illness and even loss. Most common water quality parameters are Ammonia, Nitrite, Nitrate, and pH. All may vary over time and all are invisible to the eye which is why it is important to test weekly. Testing aquarium water weekly will aid in keeping your most important water parameters within the proper range for your aquarium. Choose from a wide range of API testing options, such as our popular FRESHWATER MASTER TEST KIT or 5-IN-1 TEST STRIPS, for accurate water evaluation. Regular testing will help you easily determine your aquarium conditions.
Find Your Ideal Testing Style!

Your API Test Options
Choose the test method that works best for you. Whether you’re a bit pressed for time, or you prefer to measure your parameters on a more in-depth scale, or you only need to test one or two specific parameters, API has what you need!

Dip and Read
Just dip a 5-in-1 TEST STRIP in your aquarium, swirl twice, and compare to our color chart for fast and accurate results.

The Scientific Approach
For more detailed analysis, use the FRESHWATER MASTER TEST KIT, POND MASTER TEST KIT, SALTWATER MASTER TEST KIT, or REEF MASTER TEST KIT for precise readings of parameters.

Pick One (or Two)
Need to check your phosphate levels? What about ammonia? API offers specific test kits to test many different parameters, from general hardness and copper to pH and nitrate. Grab the one you need for a streamlined approach to testing.