How does a swimming pool filtration system work?

Posted by Nick Lewis on 26.02.2024

Keen to have the pool filtration system explained by an expert? You’ve come to the right place!

At the Chemsol Group, our team of fully qualified pool engineers have designed, installed, and maintained countless pool plant rooms for both residential and commercial customers.

To help you understand what’s involved in keeping your pool or spa clean and clear, we explain the entire swimming pool filtration process in more detail below.

What is a pool filtration system?

A pool filtration system, as the name suggests, is designed to clarify the pool water by filtering out debris and other unwanted particles using a porous material.

Essential for sanitation and enjoyment purposes, there are three main types of pool filtration system - sand, DE (diatomaceous earth), and cartridge.

Each type of pool filtration system works slightly differently, but their common aim is to remove dirt, debris, and bacteria to help prevent unwanted issues such as the spread of infection and growth of algae.

What's involved in the swimming pool filtration process?

As mentioned above, the swimming pool filtration process varies slightly depending on the material used to purify the water. However, no matter which type of swimming pool filtration system you use, the basic process will remain the same.

The pool filtration system is explained in more detail for each type of pool filter below.

Sand pool filtration system process

To filter out dirt and debris between 20-40 microns, sand pool filtration systems use slotted lateral pipes to evenly disperse water across a chamber filled with sand. The sand allows water to move through, while retaining any impurities.

DE pool filtration system process

DE pool filtration systems use sponge-like organisms in diatomaceous earth powder to filter out impurities between 3-5 microns. This powder is used to coat a selection of grids that the pool water is passed through, catching dirt and debris in the process.

Cartridge pool filtration system process

With the ability to remove impurities as small as 10-15 microns, cartridge pool filtration systems use a layer of synthetic fabric (a cloth-type material) folded into pleats. Pool water is simply pumped through this fabric layer to filter out dirt and debris.

Contact the Chemsol Group for professional pool plant rooms

Here at the Chemsol Group, the team of fully qualified pool engineers understand that your swimming pool is only as good as the plant room – and all the filtration, sanitation, and heating equipment it houses!

Thanks to an in-depth knowledge of the swimming pool filtration process, we can design, install, maintain, and service a wide range of spa and pool plant rooms, both in commercial and residential environments.

If you’d like to find out more about the services available at the Chemsol Group or the swimming pool filtration process, you can get in touch by giving us a call on 01492 582 888.

Alternatively, you can also reach out by emailing your enquiry to or heading online to fill out and submit our online contact form. No matter how you choose to get in touch, we hope to learn more about your specific pool plant room requirements soon!

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