Many aquatic flora and fauna are sensitive to the presence of Chlorine in water sources. To assure a safe environment it is critical to provide the highest quality water supply free from contaminants. Instant DeChlor is a highly concentrated formulation that provides instant removal of Chlorine with only one drop per gallon. It also reduces the toxicity of heavy metals such as copper, cadmium, mercury, silver, zinc, lead, nickel, manganese, and sodium selenate which may be harmful to aquatic life. For Chloramine add two drops per gallon. "The Choice of Aquarists for over 50 years." Available Sizes: 1/2 oz, 1.25 oz, 4.0 oz, Quart