Controls the growth of many types of algae in freshwater aquariums. Effectively resolves green water" algal blooms and string or hair algae (Cladophora). Helps keep your aquarium water crystal clear appearance. Concentrated liquid form for easy use. Comes ready to pour no mixing is required. For freshwater aquarium use. 8 oz treats 2 400 gallons. Not for use with aquariums housing freshwater crustaceans including shrimp crabs and lobsters."