Starbrite Aqua Water Treatment Freshener Use Starbrites Aqua Water Treatment and Freshener to maintain perfect drinking water quality in boats and RVs. This biodegradable formula safely prevents water from taking on chlorine, sulfur, plastic, or metal odor or taste. Features Prevents foul tasting or smelling potable water. Can be used as often as needed to ensure quality of bathing and drinking water and ice. 1 fluid ounce treats 20 gallons of water. Directions Before adding fresh water to tank