pool and spa filter top view

How to Clean Your Pool or Spa Cartridge Filter

If you want to get the most your of your pool or spa’s cartridge filter, cleaning it out at least every week will help a great deal. By cleaning it, the filter isn’t overloaded with dirt, debris, and bacteria. A clean filter can do its job better and avoid premature disintegration of the filter material. This, in turn, ensures the pool stays cleaner. By removing the gunk from the filter, it can clean more efficiently and catch smaller debris.

Tools you will need:

  • A stiff bristled brush
  • A large bucket with a lid that closes tightly
  • A water hose with a spray nozzle
  • Liquid chlorinator or cartridge cleaning solution


  • A vacuum cleaner or air compressor

A note on safety:

Any organic material on the filter can potentially be irritating, so be careful and avoid breathing the dust when you remove it with a brush or compressed air. Using chlorine is dangerous and you should keep it or any solutions of it out of the reach of children. Do not splash it on your clothes and avoid direct contact with skin. Be very cautious when pouring the chemicals. Always add them to the water, never add water to concentrated chemicals.

How to clean the cartridge filter

Before you clean the filter, make sure you verify the process with the manufacturer. If they have their own cleaning instructions, follow them. After you pull the filter from the assembly, you’ll begin by removing any large debris and organic material by spraying it off with water. Don’t wait too long after removing the filter. If it’s allowed to dry out, dirt and debris will set into the filter and make it much harder to clean. Once all the material has been sprayed off, you can let the filter sit out, preferably in bright sunlight, which can kill off any algae spores that are on the filter. Let the filter dry completely out. Next, use a brush to remove loose particles. You can also tap the filter. Once the filter has been brushed off, it’s time to use a cleaning solution or mix a chlorine solution to soak the filter in. Plan to keep the filter in the solution for at least a day, even up to three or four days. It may be handy to have multiple filters to switch back and forth as you clean them. You can buy cleaning solution at your local pool supply store or you can mix chlorine and water. Use one part pool chlorinator to six parts water. Put the water in the bucket first and then pour the chlorine into it. Be very careful during this step. The bucket you use needs to have a tight-fitting lid. Once you’ve made the solution, submerge the filter and replace the lid. It may be more economical to clean multiple filters at once. Now that the filters are soaking, the cleaning solution will work to kill micro-organisms which have become trapped in the filter’s material. It will also kill any organic contaminants. After a couple days, carefully remove the filter and rinse it in a bucket of clean water. As you submerge in the clean water, also agitate the filter by quickly dipping it in and out. You should see a cloud or contaminants emerge from within the filter. That’s how you know it’s cleaned! Now place the filter into a bright, dry area to dry out. Once dry, brush it off once more. You can keep the cleaning solution for the next time. Simply replace the lid and keep it out of reach of children. The may be some sediment that collects at the bottom, but that’s normal and doesn’t mean the solution needs replaced. If you have a lot of mineral deposits in your pool water, you may also want to clean those off your filter. Confer with your local pool supply store if this is a step you need to take. If you have purchased a cleaning solution, it may also be formulated to break up mineral deposits. Your filter is now fully clean and ready to be reused. It’s a good idea to have a backup filter that you rotate weekly. It will make maintenance a little easier and allow filters to dry out completely before use.

Some tips:

  • After each time the filter is dry, brush or tap it to remove dirt. This assures that the dirt is removed and the filter is as clean as possible.
  • If you use a clarifier, you may have to clean your filters more often.
  • Keep the pool water well-balanced to make the filter’s job easier. Clean and well-balanced water means fewer organic contaminants.
  • Once clean and dry, store cartridge filters in a plastic bag to keep them clean and avoid bugs from settling in them.
  • Having multiple filters make it easy to swap out and clean them as needed.
  • Using an enzyme in your pool weekly will help maintain the water and filter. The enzymes will break down organic waste before it can build up on the filter.
Keeping a clean filter makes it a lot easier to care for the pool or spa and goes a long way in ensuring that the system is working as it should. A dirty filter means the whole assembly has to work harder, reducing its life and potentially leading to dirty water and algae blooms.

Do you know how to properly care for your pool?

We’ve created a pool maintenance checklist to make the task of cleaning and maintaining your pool a lot simpler.

You many also be interested in:

Now offering special financing options.

Subject to credit approval.