Step 4 in Building the Dream Water Garden – Selecting the Correct Pump
Selecting the correct type of pump for the water garden is imperative to maintaining a healthy pond. Listed below are a few important tips for selecting the right pump for your needs:
- The pump is the heart of any water garden. Little Giant recommends that the water garden have two pumps if you are planning a water feature (fountain, waterfall, pond ornament, etc.): one for filtration and one for the feature. Larger pumps can support filtration and a water feature at the same time.
- For ponds larger than 1,000 gallons, the water should be filtered at least once an hour. This means that if you
have a 2,000-gallon pond, you should have at least a 2,000-gallon-per-hour (GPH) pump. Water gardens less than 1,000 gallons need to be filtered 2-3 times an hour. The smaller the pond the more frequent the flow. To calculate your gallons, use this equation: L x W x avg D x 7.48 = gallons
- The height at which the water is discharged above the pond affects the amount of water a pump will move. Normally, the higher the water is pumped above the water surface, the lower the amount of water it can pump. Therefore, if the top of your stream is 5 vertical feet higher than your pond, you should select a pump satisfying your flow needs at 5 feet. E.g. 2,000 gph at 5 feet.
- When selecting the ideal pump, it is better to oversize slightly than undersize it. For example, a pump rated at 700 gph can be reduced to 625 gph, but a pump rated at 500 gph cannot produce the extra flow needed.