How to Choose a Pump for an In-Ground Pool

Finding the pump that’s the right fit for you.

Your pool pump is critical to the life of your pool. It pushes water through your system’s pool filter, helping to sanitize your water. We don’t expect you to be experts in the mechanics of it, but we do want to share with you a few things to consider when you’re trying to buy a pump for your in-ground pool.

Make Sure Your Pump and Filters Match

Because your pump and filter work so closely together, you need to make sure that the inlet and outlets are the same size for both devices. If your filter has a 1.5-inch intake line, then your pump needs to have one, too. These devices can’t work efficiently if the pump and filter don’t fit together as you’ll need them to. 

Pay Attention to Pool Volume and Other Factors

Factors like pool volume and the maximum flow rate are also important to calculate before you invest in a pump. We’ll talk about the flow rate in just a moment, but we want to draw your attention to the fact that differently shaped pools require different calculations. For “average depth”, you’ll add the shallowest and deepest ends of your pool, then divide that number by 2.

  • To find the water volume for a circular pool, you’ll need to multiply the diameter by the average depth. Multiply this number by 7.5 to express the volume of your pool in gallons.

Diameter x ((Depth of Shallow End + Depth of Deep End)/2) x 7.5 = Volume in Gallons

  • For oval and rectangular pools, you’ll need to multiply the length, width, and average depth. Multiply this number by 7.5 to express the volume of your pool in gallons.

(Length x width) x ((Depth of Shallow End + Depth of Deep End)/2) x 7.5 = Volume in Gallons

Check your calculations with Pentiar’s pool volume calculator.

Calculate the Flow Rate

Many pumps advertise their flow rate by calculating the gallons-per-minute, GPM. That stands for “gallons-per-minute,” and it will help you determine the time it will take for that pump to circulate all of the water in your pool during a certain timeframe. We recommend investing in a pump that can do this in 8 hours.

With some simple math, you can calculate the flow rate you’re looking for in a pump. First, you divide the total water of your pool by 8 hours. Next, you’ll divide that number again by 60 minutes to get the GPM. 

What We Recommend

The SuperFlo® VST Pool Pump, offered by Pentair, is specifically designed for cost-conscious but practical pool owners. It’s easy to use, will perform for a long time, and reflects Pentair’s reputation for building high-quality pool products. Calculate how much you’ll save on 

Learn More

We’re currently running a special on the SuperFlo®, and you can save up to $125. We’re also happy to answer questions for you at our Fayetteville or Lumberton locations; we observe social distancing and ask that you wear a mask. You’re also welcome to browse our Facebook page, where you can find more information about products, useful information for your pool, and more.

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(910) 425-6138

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Fayetteville, NC 28306

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(910) 738-8110

1380 Linkhaw Rd
Lumberton, NC 28358

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Saturday: 9am to 1pm
Sunday: Closed

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