Abstract: A water filtration system has a tank partially filled with a floating bead filtration media. A cylindrical diffuser is disposed in the tank and extends from the upper portion to the lower portion thereof. The diffuser in internally partitioned into a lower chamber and an upper chamber and each chamber has slots that communicate with the tank. An supply conduit delivers soiled water from a pond to the lower chamber of the diffuser. The soiled water flows through the openings in the lower chamber and into the tank, upwardly through the filtration media where it is filtered, and into the upper chamber through the openings formed therein. An return conduit delivers filtered water from the upper chamber of the diffuser back to the pond.