Oase ProfiClear Premium Compact - L Gravity Fed OCWhat is the Oase ProfiClear Premium Compact L EGC Gravity Fed? The Oase ProfiClear Premium Compact L EGC Gravity Fed is a professional compact drum filter suitable for ponds up to 140,000 litres, 70,000 litres with fish stock and 35,000 litres with Koi. This gravity fed filter can be installed 12. 5 cm above your pond's water level and offers optimum flow rates of up to 25,000lph. It can also be buried in the ground and fed from a bottom drain. This