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Not sure how to properly size your waterfall pump? Feel free to check out our online calculators
There are several factors that go into getting the right size pump for your waterfall.Β First you need to decide on your waterfall flow rate.
Waterfall Flow RateΒ
The waterfall flow rate is how much water is flowing over a waterfall or stream to achieve the desired effect.Β The more water that flows over the waterfall the louder the sound of running water will be. Here are some guidelines to help you determine the waterfall flow rate based on the amount of flow you desire.
Β·Β Β Β Β Β Β Β Β Light Flow = 100 gallons per hour (gph) per inch of spillway
Β·Β Β Β Β Β Β Β Β Medium Flow = 150 gph per inch of spillway
Β·Β Β Β Β Β Β Β Β High Flow = 200 gph per inch of spillway
Width of Spillway X Desired Flow Rate = Total GPHΒ

EXAMPLE: You want your waterfall to have a 24β spillway
ANSWER:
Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Light Flow = 24β Spillway x 100 gph = 2,400 gph
Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Medium Flow = 24β Spillway x 150 gph = 3,600 gph
Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Heavy Flow = 24β Spillway x 200 gph = 4,800 gph
You will need a pump that will be able to pump this much water at the height of the waterfall after it overcomes the head pressure.
Sizing a Pump for Your Waterfall
To determine the size pump you will need for your waterfall, you will need to know the waterfall flow rate, the length of tubing, the height of the waterfall, and the number of elbow & T fittings used.

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EXAMPLE:Β Your waterfall is 24β wide and requires 3,600 gph and is 4β above ground level and has 10β of tubing and 2 elbow fittings.
ANSWER:Β 4β high + 1β for tubing + 2β for fittings = 7β of head
You will need a pump that provides 3,600 gph at 7β of head to achieve the desired effect of the waterfall or stream.
For more information:Β proper pump selection