Effective yet compact filter that can be buried and can keep a body of water up to 4,500 litres (1,000 gallons) clean.These pond filters are just in and incorporate the last technology. No need to take the lid off this filter - simply move the rocker switch from \'clean\' to \'waste\' and the pump water switches direction creating a backwash to flush debris to waste. Separate waste outlet - unlike inferior pond filters available elsewhere at this price point, this filter has a water inlet, a water outlet and a waste outlet. Compare this to other filters on the market - can you see 3 separate \'tubes\' coming out? If there is only 2 then this means additional maintenance required. Ensure you choose the best deal - this is our star offer. NOTE: UVC bulb included.