These high-performance protein skimmers feature a design specifically for use by hanging on the edge of your aquarium. The protein skimmers have a very simple design but perform a very important task in your aquatic tank. Each protein skimmer comes with a submersible needle pump, using needle wheel technology to generate the best bubbles. The surface tension of these bubbles attracts organic waste and carries it through the column; then this waste is "skimmed" into a collection cup for disposal. All our protein skimmers come with an integrated needle wheel pump. This type of pump introduces air through a venturi air tube, and when water is drawn through the needle wheel impeller, it cuts the incoming bubbles into a fine mist. This improves the skimmer's performance. Please ensure that the skimmer's outlet pipes are fully submerged for the device to function properly. The water level should not be lower than the maximum depth from the edge mentioned below. Suitable for use in water tanks (as a hanging system).