Water Garden Gems Sludge Pellets are, by far, the fastest working organic sludge digester on the market! Watch the sludge disappear in a matter of days! Completely safe for the environment, fish, and plants, these sludge pellets feed on biowaste, removing the need for you to drain your pond and manually clean it! No more pond draining! No more sludge stench! No more mess–let the pellets keep your pond floor clean!