ConstantClean+ (plus) is Marquis’ flagship water-management system. It combines ConstantClean, the most thorough and efficient filtration system on the market, plus (+) a twofold sanitation system. ConstantClean includes SmartClean software, which automatically schedules a high-volume clean-up cycle twice per day, cleaning 100% of the water over 34 times. You can set it and practically forget it for up to four to six weeks. The system automatically schedules an extra cleanup cycle 30 minutes after each hydrotherapy session. The end result is an elegant and convenient design able to clean more water, more thoroughly, in far less time than competing hot tub brands, with a lower concentration of sanitizer chemicals in the water.