Multi Media Filters are used for removal of suspended solids or particulate matter suspended in water by passing water through a bed of granular medium. As the water passes through the filter bed, the suspended matter in the water is removed by a variety of removal mechanisms such as straining, sedimentation, interception, and flocculation. The suspended or particulate matter arrested within the filter is removed by the shear forces created by backwash water as it moves up through the expanded bed. Surface washing with water and air scouring are often used in conjunction with the water backwash to enhance cleaning efficiency. Typical media used in this case is filtering sand along with anthracite.