Kordon Rid-Ich Plus treats diseases caused by ich and other common protozoan parasites. Safer than 100% malachite green for aquarium fish, including catfish, loaches, and tetras. Do not use on elephant nose fish (mormyrids) or stingrays. Do not use with other medications. For freshwater and marine aquariums. 1 gallon size treats approximately 7,680 gallons.