Most water problems are invisible to the eye. Quickly measure and modify the four 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 colour card. Just fill the test tubes, add the test drops and compare results to the colour card. Then follow the recommendations on the card if action is required. This kit is suitable to test both tap water and aquarium water, for the four main parameters that can affect the health of all freshwater fish in an aqaurium: pH, Ammonia, Nitrite and Nitrate. The tests are highly accurate and economical as the kit totals over 800 individual tests. The kit includes all the tests required to fully monitor the nitrogen cycle in an aquarium and includes computer-calibrated, laminated colour test cards, 4 glass test tubes and a useful test tube holding tray. The test also contains a complete, step-by-step instruction booklet, including information on how to correct any potentially unsafe water conditions, should you experience this. For an informative and detailed explanation of the importance in testing your aquarium or pond water please read our article, Freshwater Aquarium Water Quality.