SeaKlear Spa-Sanitizing Granules, 5-Pound Spa-sanitizing granules balanced and quick-dissolving form of chlorine that effectively disinfects the water Scatter approximately 3 teaspoons of SeaKlear spa-sanitizing Granules per 500-gallon of water over the surface of water After each use, shock treat with 9 teaspoons of granules per 500-gallon of water to control odors and algae Available in 2-pound