Fluval Smart Pump Technology is the key to providing optimal filter performance. Smart Pump employs an electronic circuit board to continually monitor the pump. Impeller speed and force are constantly measured to ensure powerful output and energy efficiency. Smart Pump Technology also manages the FX6 self starting feature and evacuates air that may enter or build up within the filtration system. On a 12 hour cycle the pump will pause and allow trapped air to escape, ensuring the best filtration efficiency at all times. The FX6 compact, super capacity canister processes and circulates 2130 Litres of water every hour and accommodates the stack of media baskets with a capacity of up to 5.9 litres of media. The FX6 canister features a combination of precision engineered baskets to eliminate any water by-pass. Designed at a height of only 54cm, FX6 fits under most aquariums. The lift-out stack of media baskets is at the heart of Fluval multistage filtration. These large capacity baskets will hold a total of 5.9L of media and enable you to stack filtration media in the precise combination of layers that will work best for your aquarium. Each one is lined with a foam insert for effective mechanical pre-filtering. the instant release T-handles let you lift and separate the basket stack quickly and easily, making routine maintenance simpler.