Orthos Liquid Systems, Inc., (ORTHOS) announced today the release of its MAXIMUS™ “free-flow” filter underdrain, constructed of robust, 10-gauge stainless steel (SST). Chemically-anchored to the filter floor using SST hardware for quick installation, the patent-pending MAXIMUS features a low, 6” profile that provides increased filter media depth or operational freeboard in retrofit applications. Equalizing orifices between nozzle plate supports provide free-flow of water and air across the entire underdrain plenum footprint, eliminating the flow distribution and pressure differential problems associated with plastic block and triangular lateral style systems. Orthos Type D nozzles with built-in pressure differential are installed into the MAXIMUS plates on 6” centers each way to further ensure excellent distribution and to cast aside problematic gravel or other support media. Long-lived gaskets and SST hardware seal adjoining nozzle plates, the plates to the perimeter frame, and the frame to the filter floor to fully encapsulate MAXIMUS.