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Use the table below to select the correctly sized item. If you have any difficulties deciding which size is right for you, contact us by email or phone and we will be very happy to assist you.
Due to the extremely lower power consumption of these pumps their performance is very sensitive to back pressure, to allow for the effects of friction, we advise that you should add 0.05m of head for each metre of 50mm flexible pipework used, so for example if you have 6m of 50mm flexible pipe, this would be equivalent to 0.3m extra head lift. We strongly advise against using flexible pipework smaller that 50mm.
What is Effective Volume ? The effective volume is the quantity of water in your pond, plus an allowance for shallow and or ponds exposed to high levels of sunlight. Both of these situations will result in a higher than normal algae growth, and fish pollution. We advise that to ensure your that your equipment is correctly sized, the effective volume be considered the minimum size for the equipment you select. However do remember to check the details of the product you are interested in, to ensure that there are no other allowances or consideration specific to that product are required.