Fluval U4 Internal Aquarium Filter The Fluval U4 Internal Aquarium Filter is a top-of-the-line filtration system, perfect for maintaining a healthy and clean aquatic environment. Its advanced technology and design effectively remove waste and impurities, promoting a thriving ecosystem for your fish and plants. Experience unparalleled water quality with the Fluval U4 filter. For aquariums from 130 L to 240 L(34 to 65 U.S. Gal.) 3 Stage Filtration: Stage 1 foam removes large particles. Stage 2 poly/carbon cartridge traps fine debris, improves water clarity and removes impurities.  Stage 3 BIOMAX provides optimal biological filtration efficiency. • Designed for aquariums up to 65 US Gal / 110 L • Use as a primary filter for smaller aquariums, or supplementary filter for larger aquariums • Position horizontally for shallow tanks, larger tanks with low water levels, or to create a decorative waterfall feature • Position vertically against aquarium wall to create currents or customized flow patterns • Convenient flip-top lid allows for quick and easy access to filter cartridge for maintenance or replacement • Adjustable 3-way flow control • Top Output for circulation and oxygenation, Integrated Spray Bar for a gentle even flow, and Bottom Output for deepwater agitation • BIOMAX biological media included • Made in Italy • Ideal for freshwater, saltwater and reptile environments • Australian Plug and Approval