API Ammo-Lock Freshwater & Saltwater Aquarium Ammonia Detoxifier is specially formulated to instantly detoxify ammonia, chlorine, and chloramines in both freshwater and saltwater aquariums. Ammonia is continually released through your finned friends’ gills, urine and solid waste, and it can also be released from uneaten food and decaying organic matter. The effects of ammonia can be harmful and potentially fatal to fish, depending on how much is released. While this treatment does not remove ammonia from the water, it converts it into a non-toxic form, keeping your underwater buddies safe. While API Test Kits (sold separately) will show a reduction in ammonia, a 25% water change is still recommended after dosing. If your aquarium does test positive for ammonia, do a partial water change and then neutralize the ammonia with this fast-acting formula. API Aquarium products make it easy to keep your aquarium in good condition, so your fish can stay happy and healthy.