## How Do I Properly Size a Pump to Create the Waterfall I’m Looking For? – Water Garden Q & A

Q: How do I properly size a pump to create the waterfall I’m looking for? – Several Customers

A: We get this question asked to us quite a bit. The following process will help you in determing the correct pump size for a waterfall:

Step 1: Determine the Head Pressure (Head)

Head equals the total number of feet from the top of the waterfall to the water’s surface. For example: Let’s say that height is equal to 5′.

Step 2: Determining Desired Water Flow
In general, you will need 1,500 gallons per hour (gph) for every 1-foot of waterfall discharge for an average flow. The discharge is considered where the water enters back into the pond. For example: Let’s say the width of our waterfall is 2′. This would mean we need a pump of approximately 3,000 gph.

Step 3: Putting It All Together
In our example, our head pressure is 5′ and the approximate gph of our desired pump is 3,000 gph. This means would need a pump that would pump 3,000 gph at 5′ of head.

Other Notes:

• For a heavy waterfall flow, use 2,000 gph per foot of waterfall discharge.
• For a lighter waterfall flow, use 1,000 gph per foot of waterfall discharge.
• If the tubing from the pump to the waterfall is greater than 10′ then it is recommended to add 1 foot of head for every 10′ of tubing.
• We also have a calculator on our website to help calculate this formula for you. Click here to view the calculator.