Abstract: A siphon transfer, cooling tower sump water cleaning device, which has a cleaning nozzle attachment (20) connected to an extension tube (32) and a collecting chamber (44). The collecting chamber has a drain hose (52) threadably attached on the end and the entire device is placed under the sump water (38) of a cooling tower (34) for priming. The hose is placed below the water level and the nozzle is scrubbed against the bottom of the cooling tower sump (36). As debris and foreign matter is dislodged and is in solution with the water siphon action takes place drawing the mixture into the tube (32). At the end of the tube the inside diameter increases slightly in the collecting chamber and abruptly, yet smoothly, increases the velocity pressure in an elipsoidal shaped converging nozzle (50) where the increased velocity draws the debris through the remaining hose (52).