Patent ID: 8800496

Claim:
A pre-filter unit for a water circulation pump, comprising: (a) a pump intake pipe having an aperture defining an area and a first port for connecting said pump intake pipe to said circulation pump; (b) a water supply pipe having a second port for connecting said water supply pipe to a water source; (c) at least one water supply pipe extension connected to said water supply pipe comprising: (1) a rotating section having nozzles through which water from the water supply pipe exits, (2) a non-rotating section, and (3) a water motor interposed between said rotating section and said non-rotating section; (d) a screen cage surrounding said pre-filter unit having a front, back, left, right, top and bottom sides, at least two of said sides having a filtering surface configured to collect algae and debris; (e) a biological cleaning mechanism on the outside of said screen cage; and (f) a frame having a length disposed beneath and elevating said pre-filter unit; wherein said pre-filter unit draws water into the circulation pump from at least two sides of said cage; wherein said pump intake pipe and said rotating and said non-rotating sections are parallel to each other and to the length of said frame; and wherein the at least one water supply pipe extension is a mechanical self-cleaning mechanism configured to loosen algae and debris impacted in said filtering surfaces.