How To Size an Above Ground Pool Pump and Filter System

Things You’ll Need

• Above Ground Pool Pump and Filter
• Above Ground Pool Pumps

Step 1

Let's start with the pump first. Above ground pumps are much simpler to size than that inground counterparts because you mainly are concerned with the size of the pool. We'll break up the pool sizes into the categories of round and oval, with the suggested horsepowers per size.

Step 2

Round Pools: The chart shows the normal manufacturer pump sizing recommendations for pool sizes. The horsepower overlaps on the “tweener” sized pools 15’ is a small to medium, and 27’ is medium to large.

Ranges:

• ¾ Horsepower: 8’ to 15’ Round
• 1 Horsepower: 15’ to 24’ Round
• 1-1/2 Horsepower: 24’ to 36’ Round

Step 3

Oval Pools: Similar to the round pools, the horsepower recommendations overlap for some models. If your pool falls in one of these overlap areas, then consider how much swimmer traffic you expect. Light to moderately used pools, choose the lower HP, for higher swimmer loads, choose the step up.

Ranges:

• ¾ Horsepower: 12’ X 17’ to 12’ X 24’
• 1 Horsepower: 12’ X 24’ to 15’ X 27’
• 1-1/2 Horsepower: 15’ X 27’ to 18’ X 33’

Step 4

Reasons to step up horsepower: Longer than standard plumbing lines and/or pool accessories may require you to make the jump to the next highest horsepower to ensure proper flow rates. Common causes for larger pumps

• Suction line from the skimmer to pump is longer than 15-feet
• You’re planning to use a suction cleaner, e.g. the Hayward Navigator, The Pool Cleaner, and Kreepy Krauly
• Adding solar panels, especially ones mounted on roofs or fences increase the strain on the pump, requiring extra HP oomph

Step 5

Now onto filters.

If your pool falls into one of the categories in the previous step, causing you to up your horsepower. I'd strongly recommend following suit, and going up a size for your filter.

Step 6

Sand
Round:

• 8’ to 15’ Round: 14-Inch Tank & Up
• 15’ to 24’ Round: 16-Inch Tank & Up
• 24’ to 36’ Round: 18-Inch Tank & Up

• 12’ X 17’ to 12’ X 24’ - 14-Inch Tank & Up
• 12’ X 24’ to 15’ X 27’ - 16-Inch Tank & Up
• 15’ X 27’ to 18’ X 33’ - 18-Inch Tank & Up

Step 7

Cartridge
Round:

• 8’ to 15’ Round:- 50 sq. ft & Up
• 15’ to 24’ Round - 75 sq. ft & Up
• 24’ to 36’ Round - 90 sq. ft & up

• 12’ X 17’ to 12’ X 24’ - 50 sq. ft & Up
• 12’ X 24’ to 15’ X 27’ - 75 sq. ft & Up
• 15’ X 27’ to 18’ X 33’ - 90 sq. ft & Up

Step 8

DE
Round:

• 8’ to 24’ Round - 15 sq ft & Up
• 24’ to 36’ Round - 20 sq ft & Up

• 12’ X 17’ to 15’ X 27’ - 15 sq ft & Up
• 15’ X 27’ to 18’ X 33’ - 20 sq ft & Up

Step 9

Now we have a window of filter sizes we can consider four pool, let’s think about variables that may cause you to upsize your filter. The larger the filter the longer you can go between cleanings. Oversized filters can hold more dirt without sacrificing flowrate or spiking filter pressure.

• If you are the party pool in your neighborhood, that means more swimmers and inevitably more dirt. If you don’t want to spend the day after each part doing pool chores.
• Larger filters also have higher flow rate capacities, this makes for lower back pressure compared to the smaller models. Less backpressure makes for less stress on the pump, filter and plumbing as a whole.