Pond pumps are electrical, recirculating, submersible pumps used to power garden ponds and pond filters. They are designed for continuous use, unlike sump pumps that run intermittently, so energy efficiency and durability are important considerations. Pond pumps require a waterproof power cord, which is usually included in the pump kit. Pumps are installed underwater, but do not generally produce any distracting noise. The size of the pump is based on the size of the pond.

Pond Pump Size

The size of pond pump required to power your garden pond is determined by the size of the pond itself. Pumps are either rated by gallons per hour (gph) or gallons per minute (gpm). The pump for your pond should be capable of circulating at least half of your pond's water volume every hour. For example, if your pond holds 500 gallons of water, it should be powered by a minimum 250 gph pond pump.

Adding Height to Your Pond

If you are adding height to your pond, such as a waterfall, the height and width of the waterfall and the flow rate of the pond filter must be considered to determine the correct pond pump size. If you are adding a very high or very powerful waterfall, it may be in your best interest to power the pond filter and waterfall with separate pumps, as the waterfall will move faster than the pond water needs to for filtration.

Calculating Pond Pump Size

The pump size required by your pond is directly related to the number of gallons your pond will hold. The pond pump must be of ample gph to properly aerate water, and you can use more than one pump. For larger ponds, say 2,000 gallons, it may be more cost-effective to purchase two 500 gph pumps rather than one, 1,000 gph pump. Using more than one pump to circulate the water in the pond is often preferred when water features, such as waterfalls, are included in the layout of the pond.

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Formulas to Build Garden Ponds and Fish Ponds

Pond and Pump Calculations