Chemical absorption media that safely removes a broad spectrum of organic waste, copper, metal ions, and odors. Also functions as an ion generator and exchange unit that keeps the pH at a safe and constant level. Indications: treats up to 40 gallons for up to 6 months. Use 2-10 oz. units for 40 to 100 gallons, above 100 gallons add 1-10 oz. unit for every additional 25 gallons.