At some time or another just about every aquarist has a battle with some type of surface scum. The method below is the best way that I have found to keep the water's surface clean and clear.

Purchase a piece of PVC pipe an inch or two longer than the length of the intake pipe on your filter. Place a cap on one end of the pipe. Attach two suction cups to the pipe so it will stick to the back of the tank.

Now attach the pipe to the tank and feed the filter's intake pipe into the PVC pipe. Place the top (open end) of the pipe about one half inch (1.25cm) below the water's surface. Now the intake will draw water from the surface like a skimmer. The scum will be collected in the filter.

		Filter intake
		________[ ]_________ Water Level
      			[ ]
		      { [ ] }
		      { [ ] }
		      { [ ] } PVC Pipe
		      { [ ] }
		      { [ ] }
		      { [ ] }
		      {     }
		      _______ End Cap

If the tank has a black background and you use black PVC it is nearly invisible. A similar PVC tube can also be set up to hide heaters and other equipment. These covers work well for catfish that burn themselves on the heater and large aggressive fishes that like to break heaters and/ or filter intakes.