The API® Ammonia Test Kit measures ammonia levels to help prevent fish loss, as ammonia is the primary cause of stress and death in tropical fish. Ammonia is released into the aquarium in the form of uneaten food, decomposing organic matter, and when fish release it through their gills, urine, and solid waste.

The API Ammonia Test Kit is a mercury-free test, suitable for both freshwater and saltwater fish, and measures ammonia levels from 0 to 8 ppm. It contains 130 tests and includes two test solutions, easy-to-read instructions, a glass test tube, and two color charts.