Tap water containing chlorine or chloramines is harmful to fish. Additionally, fish, decomposing algae, plants, and uneaten food matter produce toxic ammonia - the number one killer of pond fish. PondCare Ammo-Lock will neutralize 7.0 ppm of chlorine, 3.0 ppm of chloramines, and detoxify 3.0 ppm of ammonia. This effective solution will hold ammonia in a non-toxic state until converted by the natural cycling of the pond's filtration system. Ammo-Lock ammonia detoxifier will help keep you beautiful pond's water safe for all it's precious inhabitants.