The SBR Decanter design is based entirely on gravity and differential pressure. The decanter, which floats up and down on the changing water surface level with the help of pontoons, has evenly distributed decanting holes to create an even and low-velocity flow. The state-of-the-art design utilizes multiple orifices to keep velocities at a minimum and pulls treated effluent from just below the surface to minimize the possibility of entraining floatables. Our patented solids excluding design effectively prevents suspended solids from entering the decanter during aeration and agitation without the use of conventional valves or pumps.