Penguin Bio-Wheel Power Filters deliver effective, easy, 3-stage aquarium filtration without the hassle of air pumps, valves, and tubing. Convenient Rite-Size Filter Cartridges come ready to use with each filter to mechanically and chemically remove waste, discoloration, and odors. Biological filtration is provided by the revolutionary Bio-Wheel which has been proven best at removing toxic ammonia and nitrites. Certified flow rate of 75GPH, perfect for aquariums up to 10 gallons