GROCO SWEETANK Odor Neutralization System - 24VSWEETANK Odor Neutralization System 24V THE CONCEPT The SWEETTANK concept has been developed to stop odors in yacht and RV holding tanks without the use of chemicals or filters. SWEETTANK is standard equipment on THERMOPURE 2 Type I MSD, in GROCO Type III MSD, and is offered in several retrofit kits to fit existing holding tanks. HOW IT WORKS Aerobic and anaerobic bacteria coexist naturally in raw sewage, but it is the anaerobic bacteria that produce