Hozelock 1800 Air Pump - 320LPH High performance, reliable air pump for large fish and koi ponds. The use of an air pump within your pond helps to increase oxygen exchange which benefits both your live stock and your pond's filtration system. Beneficial bacteria require oxygen to metabolise. Increasing the oxygen levels within the pond, especially in the filter if at all possible, will ensure that as large a population as possible of beneficial bacteria can develop - increasing the filter's efficiency and improving your water quality.
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