Abstract: 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 (or some mix of the two) 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.