Specially selected bacterial strains in API POND-ZYME SLUDGE DESTROYER bacterial cleaner immediately begin breaking down fish waste and dead algae that cause cloudy water, sludge build-up, and debris that clogs pumps and filters. Through enzymatic action, POND-ZYME SLUDGE DESTROYER bacterial cleaner reduces pond maintenance and keeps pond water clean and clear. It is a 100% natural product, & safe for all pond fish, plants, and wildlife. Initial dose at Spring start-up and end of season dose: add two scoops per 200 gallons of pond water twice a week for 2 weeks. Maintenance dose: add one scoop per 200 gallons every 2 weeks.