Scum is a thick film of spongy matter floating on the surface of drain water found in the tanks of water treatment facilities (such as septic tanks). Suspended matter, fibers, oils and fats, and bacteria in the drain water are floated up by the gases generated from decayed or fermented organisms in the water and become scum. Equipment which removes such scum is called a scum skimmer. It rotates a slotted pipe using the stroke of the Power Cylinder and only the scum on the water surface flows into the pipe for removal. It is necessary to select the appropriate specifications for harsh environments such as using 304 stainless steel as the material for the rod, end fitting, and connecting pins, providing an interlock with a manual handle, and adding an accordion pipe. A scum skimmer is mainly used in water purification centers.