How a Swimming Pool’s Filtration System Works, Part 1

There are several important components to know about if you’re a homeowner purchasing a custom swimming pool, and one such component is the pool’s filtration system. Vital for cycling through and purifying the water in your pool, filters play a big role in the health and safety of everyone using the swimming pool.

At Packman’s Pools, we’re happy explain the filtration system in detail for any of our new swimming pools. In this two-part blog, we’ll go through several of the standard components that are generally used in a pool’s filter, a few options that might be available to you in certain areas, and some other important details to know.

swimming pool filtration system

Skimmer and Main Drain

For starters, your pool needs to be able to pull in water from the main swimming area to begin the process of cycling it through and cleaning it. It does this from two primary sources: The main drain and the skimmer.

The main drain, as the name suggests, is a large drain that generally sits at the bottom of the pool. The skimmer, on the other hand, is a square or rectangular opening near the surface of the pool, right beneath the coping (some pool water will naturally sit inside the skimmer when it’s oriented properly). Both these sources pull in water toward the pump and filter.

One note here: A greater and greater number of new pools today are being made without main drains included. These options simply include skimmers only – this is common for smaller pools in particular, which often don’t need a main drain for effective filtration.

Pool Pump

Once water has been pulled in by the main drain and/or skimmer, it reaches the pump area. Most pool pumps show a large, round front section that extends backward – this front section is known as the strainer pot, which, as the name suggests, begins straining impurities out of the water. It catches larger pieces of dirt and debris before sending the water along to the filter for a more detailed clean.

Pool Filter – Types and Uses

From the pump, water moves to the pool filter. This is one area where there may be some choices available – pool filters generally come in three styles:

  • Cartridge filter: The most common type for modern pools, cartridge filters use large sheets of cloth or paper folded accordion-like into cartridges that catch debris. Certain pools will use single-cartridge filters while others will require more than one.
  • Sand filter: A tank full of sand, with pipes that send water evenly through the sand, which catches debris.
  • DE (diatomaceous earth) filter: Filters that use grids covered in “DE powder,” essentially a form of fossil dust, that can catch debris and filter it out.

For more on the filtration process in your pool, or to learn about any of our custom swimming pool options, speak to the pros at Packman’s Pools today.