Abstract: A filtration system for cleaning contaminated fluids having input means disposed tangentially of a cylindrical filter surface and simultaneously sweeping said surface and providing a fluid flow therethrough and backwash means having one or more nozzle bearing standpipes adapted to simultaneously rotate within and axially reciprocate spray nozzles relative to a cylindrical filter assembly to dislodge particulates therefrom either concurrently or independently of the flow of contaminated fluid therethrough.