Perfect pond solution for ponds sized up to 15,000 litres 3,300 gallons. By simply twisting a knob on the filterit automatically cleans itself! In the 'run' position the water undergoes a 4 stage purification process. Simply turn the knob to clean and the foams are squeezed by up to 1000lb of water pressure forcing out pond sludge. The back flushed dirty water is then pushed out through the second waste outlet typically down the drain or flowerbeds. The filter also boasts a built in 13w uvc and guarantees clear water for ponds up to 15,000 litres. Figures based on pond in full shade with water plants 7,500 litres for ponds in full sun. The pump supplied is from the same manufacturer, features very low running costs and is highly reliable.this set contains the following components please click link below for more information• fish mate 15000 pressurised filter br • fish mate 9000 pond pump