Abstract: Embodiments provide a pool filter cleaning system that comprises an elongate tube having a first end, a second end and length in a longitudinal direction; a hose connector configured to connect to a supply of water under pressure, the hose connector is attached to the first end of the elongate tube. A spray nozzle is located at the second end of the elongate tube such that an outer surface of the spray nozzle and the elongate tube establish a substantially smooth continuous outer surface. The spray nozzle of an exemplary pool filter cleaning system comprises at least one water oscillation chamber configured to oscillate or pulsate fluid flow through the spray nozzle such that fluid output from a plurality of spray nozzle fluid outputs is oscillated or pulsated at a sonic frequency and in directions that have both a radial component and a longitudinal component away the second end.