Tetra Whisper Internal Power Filters is three Filters in One. The Whisper in-tank filter adjusts easily to high or low water levels with mounting suction cups and/or bracket. http://www.petco.com/prod
Tetra Whisper 20i Quick Set Up Guide Before we begin, it's a good idea to lay out all of your parts on a clean clear surface and to review the safety instructions and helpful hints in the manual. Insert the filter cartridge and bio scrubber into the internal filter. The front of the bio scrubber should face the front of the internal filter. Attach suction cup to the back of the filter. Hang the filter box on the inside wall of the aquarium frame. Ensure that the top edge of the filter should be above the water level and the bottom of the filter should be at least an inch above the aquariums gravel. This setup was done dry, but Tetra encourages you to use water for your filter to run effectively from startup.