Q: I am building a pond with a waterfall. With so many pump choices, how do I know what to choose?
Linda – Broomall, PA
A: Fun springtime project ahead! As you’re discovering, building a pond with a waterfall involves some planning and careful consideration—which includes selecting a waterfall pump. Your choice is important because it’ll determine how high you can make your waterfall and how much water will flow down it.
You want more than a trickle, right? Before you go pump shopping, crunch these numbers first:
1. Head Pressure
How high will your waterfall be? This measurement is your head pressure, which is the total number of feet from the top of your waterfall to the top of your pond’s surface. If you’re building a 5-foot-high waterfall, for instance, your head pressure is 5 feet.
Pro tip: If the tubing from your pump to the waterfall is longer than 10 feet, add 1 foot of head pressure for every 10 feet. So in the example above, if your tubing is 14 feet, the head pressure would be 6 feet.
2. Flow Rate
How much water do you want pouring over the falls? This number is your flow rate. The average flow rate is 1,500 gallons per hour for every 1 foot of waterfall width. If your 5-foot-high waterfall is 1 foot wide, you should go with a pump that moves around 1,500 GPH; if it’s 3 feet wide, you should go with a pump that moves 4,500 GPH or so.
Pro tip: If you prefer a lighter water flow, calculate 1,000 GPH for every 1 foot of waterfall width. For a heavier flow, use 2,000.
With those numbers in hand, you should have a pretty good idea what kind of waterfall pump you’ll need to buy. To make the chore easier for you, we recommend:
For lower-flow waterfalls: If you’re designing a smaller waterfall, check out The Pond Guy® MagFlo™ Pump and The Pond Guy® SolidFlo™ Pump. The MagFlo™ line includes 290, 460 and 590 GPH models with maximum head of 6½ to 7½ feet; the low-profile SolidFlo™ line includes 600, 1,200 and 1,600 GPH models with maximum head of 8 to 11½ feet.
For higher-volume waterfalls: If you’ve got a mini-Niagara Falls in the works, you’ll need a beefier pump, like The Pond Guy® RapidFlo™ or the ShinMaywa® Norus® waterfall pumps. The RapidFlo™ comes in 3,000, 4,000 and 5,000 GPH models with 20 to 32 feet of maximum head pressure. The Norus® line includes 3,300 to 11,000 GPH models with maximum head of 19 to 48 feet.
Pond Talk: What advice would you give to someone choosing a waterfall pump?