Emperor Filter Systems are advanced aquarium technology at its finest. With a revolutionary two-pump design, flow and filtration efficiencies of the Emperor's are unmatched by other filters in their class. Featuring as much as twice the filter cartridge capacity, additional chemical filtration capability, and extra large, spray bar-driven BIO-Wheel wet/dry biological filtration, Emperor Filter systems offer the aquarist a filtration system that can stand up to any aquarium they can dream of. Certified flow rate of 280 GPH, perfect for all aquariums up to 50 gallons. Uses one Rite-Size "E" filter cartridge.