Thetford AquaMax Spring Showers Holding Tank Treatment AquaMax Spring Showers by Thetford is holding tank treatment that utilizes advanced enzymes to breakdown residue and remove odors. The enzymes also speeds up waste breakdown to help prevent clogs and future residue buildup. The formula has bee ndesigned for RV, Marine, holding tank, and septic system safe while being campgroundmarina friendly. AquaMax is available in quart, gallon, and 8oz 6 pack options. Features Available in quart 96635, G