a bio - reactor made according to this invention uses low temperature aerobic composting to decompose bio - compostable material . the reactor includes mixing paddles with wiper blades which aerate and agitate a set of plastic resin biochips which house microorganisms and cause the chips to come into contact with bio - compostable material . a water pipe located toward the upper portion of the bio - reactor delivers fresh or recycled water and the bio - reactor cycles between a water cycle and a non - water cycle . agitation also cycles on and off . perforated bottom screens limit the size of the composted material exiting the bio - reactor . the wiper blades , which may be brushes , continually wipe the bottom screens and work to prevent blockage and build - up of debris within the bio - reactor .