Pond Pumps

CAPACITY

We offer a range of pumps with varying capacity. There are two key measures to consider.

The distance the water is to be pumped (Head Heightin metres) and the flow rate (Litres/Hour)

HEAD HEIGHT

The distance the water is to be pumped is called the Head Height and is measured as the maximum vertical distance (in metres) from the water surface to wherever the water is being pumped to. If the water is also being pumped horizontally add 10cm for each metre of travel, this is due to resistance in the pipe.

FLOW RATE

The flow rate is the number of litres per hour.

To calculate your requirement you will need to calculate the litres of water in your pond. This is width x height x depth (all in metres) x 1000 to convert into litres.

So for a rectangular pond 3m x 5m x 0.75m deep would have a capacity of 11,250 litres. If you have a variable shape then work out average dimensions and/or break the pond into sections and then add together each calaculation

TO CALCULATE YOUR FLOW RATE USE THE FOLLOWING AS A GUIDE

For a pond with many large fish and a few plants (e.g. A Koi Pond) it is recommemded to change the water once per hour. So the flow rate = the pond volume of water in litres

For a pond with an average amount of fish that are smaller and some planting (e.g. A goldfish Pond) its is recommed to change the water every 1.5 hours. So the flow rate = the volume of water divided by 1.5.

For a wildlife pond with a small number of fish and lots of plants then the water can be changed every 2 hours. So the flow  rate = the volume of water in litres divided by 2.

if your pond water surface receives too much sunlight then algae is likely to build up, this can be reduced by additional planting but the flow rate should be increaased to allow for this. If this is likely to be an issue then increase the flow rate by 25%.

So a pond with 11,250 litres used for Koi would need a flow rate of 11,250, and maybe 14,000 litres  if exposed to too much sunlight. For a wildlife pond it would be 5,625 or 7,000 litres with sunlight issues.

PUMP RATINGS

The pump max flow rate is the litres per hour that the pump can process, this is measured with zero head height. As the head height rises the flow rate will decrease so that at the maximum head height the flow rate is zero.

To identify which pump is suitable Use the graph for each pump, identify the flow rate based on your head height and ensure it meets your needs