Quad-Action formula for fast removal! 8 oz treats 1,600 gallons. Immediately removes chlorine, chloramine, and heavy metals often present in city water supplies. Left untreated chlorine can cause gill damage and leave fish unable to breath. Vanish will also add a slime coat protectant to the water to help fish heal wounds and abrasions and protect them in times of stress (during water changes and clean-outs) Safe for all aquatic life, birds, or domestic animals that may drink from pond.