is a biological aerobic (bacteria and air) Type II Marine Sanitation Device. Liquid and solid waste are removed from the water by bacteria naturally contained in sewage. The AHEAD TANK makes perfect environmental sense by working with nature to accelerate the normal biological process. With the addition of oxygen, the natural occurring bacteria breaks down and digest the solids. A mild disinfectant is added to kill any disease-causing bacteria prior to being discharged. AHEAD TANK has no moving parts that comes in contact with the sewage. This biological aerobic process is simple, effective, and ensures Reliable Odor Free Operation.