What Size Filter Pump is Best for Your Above Ground Swimming Pool?

Having the right size filter pump for your above ground swimming pool is critical for overall performance. If your filter pump isn’t the correct size, you’re not only affecting water quality, you’re also wasting more energy.

The problem with choosing the wrong filter pump size?

Too Small = If you’re using a filter pump that’s too small for the overall water capacity of your above ground pool, your pool water isn’t circulating well enough to remove algae buildup and debris. 

Too Big = If your filter pump is too big, the debris will completely bypass your filter altogether, which leads to dirty water. Having a pump that’s too big is also not energy-efficient since it’ll be running more often than it needs to.   

So how do you determine which size of filter pump is right for your above ground swimming pool?

Let’s “dive” in and find out! 

Choose Your Pump Type: Cartridge Filter Pump vs. Sand Filter Pump

Before you determine the correct size pump, you’ll want to decide if a cartridge filter pump or a sand filter pump is right for you.

Cartridge filter pumps work by circulating water out of the pool, through a filter and back again. They sift twice as much dirt and debris compared to sand filters because the larger filtration area catches smaller debris. 

Sand filter pumps have a longer lifespan compared to cartridge filter pumps (silica sand lasts up to three years while filter cartridges need to be replaced every two weeks). This energy-efficient pump uses silica sand instead of a traditional filter cartridge, or Polysphere Pool Filtration Balls as a lightweight alternative.  

Still not sure which one is right for you? We have a great article that explains How to Choose the Best Filter Pump for Your Needs.  

How Do I Know What Pump Size is Right? 

Now that you’ve selected a pump type, you can determine the correct size you’ll need.

Overall, most above ground swimming pools on the market are similar shapes and sizes, which makes it easier for you to know which size pump is the right one.

Your filter pump should filter all the water in your pool within six hours. This allows for optimal filtration. Therefore, you’ll need to know two numbers before you get started: water capacity and pump system flow rate.

You’ll find the water capacity on your pool’s packaging and the flow rate on the pump’s packaging.   

Don’t have your box? You can find the water capacity by calculating 90% of the volume of your pool. If you don’t already know your pool size, you can look it up online to see what the recommended water capacity is based on your pool dimensions. These won’t be exact measurements, but close enough to let you figure out the pump size you need.

Now it’s time for some math!

Once you’ve calculated the pump system flow rate you’ll need, make sure it equals (or is higher than) the system flow rate included on your pump packaging. The higher the system flow rate, the higher the filtration effect. But remember, big doesn’t always mean better, so make sure you do your math first!  

That’s it!

Now that you know how to pick the right size filter pump for your above ground swimming pool, go have a splash-tastic time! 

Need a new filter pump? Check out the assortment on our website to find the one that’s right for your above ground swimming pool.