What Happens When Your Pool Filter Is Dirty?

Filter media that is dirty will promote algae growth and place unnecessary strain on your pump as it attempts to force clean water through a clogged filter. 


Why do pool filters need to be kept clean?

Yeah, indeed! It is imperative that you clean your pool filter. There's a lot that goes into keeping your pool in good shape: shocking it, vacuuming it, shutting it for the winter, treating it on a regular basis, and, of course, cleaning your filter. Consider your home's air filters. You'd be inhaling loads of dust and dirt if you didn't alter them. You've already noticed that the longer you wait to replace your air filter, the dirtier it gets.

The same idea applies to your pool filter. Dirt and debris become stuck inside the filter bed as your pool filter performs its function, causing accumulation.


How do I know that the pool filter is dirty?

Testing the filter pressure scale on the top of the filter is the most common way to identify a dirty pool filter. If the pressure is too high, it might mean that your pool filter has too much buildup and water isn't flowing through it fast enough.


Clean operating pressure is the perfect pool filter pressure, which varies depending on the type of pool filter system you have. Most pool filter systems work best when the pressure is between 5 and 20 psi. Make a note of the pressure at which your pool filter is running when it is installed; this is your system's clean operational pressure.


If the pressure in your pool filter increases 8 to 12 psi above its clean operating pressure, it's a warning that it's time to clean it.

How often should I backwash my pool filter?

That's equivalent to wondering how long a length of string is because it depends on how much you use your pool, whether it's surrounded by overhanging trees or vegetation, and whether it's susceptible to grass clippings when you mow the lawn.


Many pool owners, however, backwash weekly as part of their summer maintenance routine, usually after vacuuming to collect any leftover particles that have been stirred up.


When it comes to keeping your pool water clean and your filtration equipment in top shape, knowing when to backwash your filter is crucial. The good news is that you can say if and when your pool filter needs to be backwashed by searching for three common signs. They are as follows:

  • Water Flow - Debris and pollutants in the filter media clogging reduces the rate at which water passes through the filter, decreasing the amount of water flowing into your pool.

  • Water clarity – murky water indicates that the filter media is dirty or incapable of catching the dirt and debris that enters your tub.

  • Water pressure – An rise in your PSI (per square inch) pressure reading indicates that your pool's filter is under strain, either due to a blockage or defective equipment.

Do You Need a Pool Cleaning Service You Can Trust?

Cal Pool Care delivers quality pool cleaning services to clients in the Tri-Valley and surrounding areas by providing them with the professional care they deserve. Great service begins and ends with experienced and friendly professionals, which is why we put so much consideration into selecting only the best to join our team. We complete projects efficiently and on schedule, and go above and beyond to form lasting relationships with our clients. Our service formula for success is consistency "same day, same time, same tech.” We offer weekly swimming pool maintenance and cleaning services. Cal Pool Care services pools, spas, and will ensure your fountains, water features and hot tubs are clean alongside regular pool service. Contact us today to schedule your first service!