Ultra Clear DeChlorinator . Excellent conditioner for aquariums and ponds with fish that removes any chlorine and chloramine that may be in the City water and promotes essential slime coat on the fish to protect gills, detoxifies heavy metals, and reduces long term nitrate build up. Well water may have more metals or too much hardness. Use for topping off your water garden pool from evaporation or filling a new water garden pool. For water garden ponds, use 2 to 4 ounces per 250 to 500 gallons of water or 10 to 12 ounces for 1250 to 1500 gallons of water. For aquariums use the smaller 4 ounce size and use one capful (5 cc) for every 20 gallons of water. Works in fresh or salt water conditions. Safe for all fish and wildlife. Use EVERY 30 to 60 days to protect fish gills and prevent nitrate buildup.