Clean 'n Green cleans any marine toilet and controls tank odors with one treatment. The rapid-dissolving 2-oz. packet effervesces in water, leaving the bowl sparkling clean. The non-toxic, non-staining formula contains 100% biodegradable granules. The enzymes break down waste and tissue for thorough tank discharge without harming bowls or seals. One 2-oz. packet treats a 40-gal. tank.