Pressure Filter is a closed cylindrical vessel either vertical or horizontal (mostly vertical) containing the filter media over a collecter system. Water flows from top downloads percolating through the media and is drawn off through the collector system at the bottom. Cycle of operation include back washing with or without air scouring, short rinse to waste and return to operation. The filter will effectively give clarified water having suspended solids to less then 20 ppm. The filter will have to be washed with Clarified water periodically.