Top Quality Filtration System for ponds up to 27,000 litres (6,000 gallons). The Oase 60000 Biotec is a professional pond filter with some truly unique features. It includes the SCREENMATIC cleaning system - a moving bed which automatically removes larger solids before they enter the main body of the pond filter. In this set the PondXpert Greenstop UVC unit is also included - this simply screws into the inlets of the filter for convenient positioning. Flow of water for the UV filter is provided by the reliable PondXpert UltraFlow Pond Pump.