Api ammonia detoxifier is scientifically proven to protect fish against harmful ammonia by converting poisonous ammonia into a non-toxic form. Ammo lock ammonia detoxifier works instantly in both fresh and saltwater aquariums, eliminating fish stress caused by elevated ammonia levels and promoting healthy gill function. Note that if your aquarium tests positive for ammonia, it is necessary to perform a partial water change first, and then neutralize the ammonia.