Ammonia is the number one killer of tropical fish. Fish continually release ammonia into the aquarium through their gills, urine and solid waste. Uneaten food and decaying organic matter also add ammonia to the water. Even small amounts of ammonia stress fish, large amounts of ammonia will kill fish. So regular testing for ammonia is important to maintain healthy aquatic life. Kit contains 2 bottles of liquid reagent, 2 laminated, computer calibrated color cards, glass test tube with snap-tight cap, step by step instructions and information on how to correct unsafe conditions. Features-1. Ammonia test kit2. Api ammonia test kit3. API test kit.