Bioguard’s best-performing algicide with dual active ingredients that combine traditional quat-based algicide and chelated copper in one powerful, high performance product. The Dual active ingredients also provide broader prevention and algae-killing power versus algicides that only contain the individual ingredients. The 72 oz. bottle provides ease of use with a 4oz. measuring cap and handle. It is non-staining and non-foaming. Apply once per week.