There are many different opinions out there on when to replace your pool filter cartridges. Typically, on a time scale alone, it is recommended between 12-24 months depending on your unique situation. Amount of usage, pool chemical maintenance, amount of debris such as dirt, leaves, and grass that get in the pool, whether or not you have pets that like to swim in the pool. All these different factors contribute to the life expectancy of a pool filter cartridge.
The indicator to best watch to determine when it’s time to clean your filter is the pressure gauge on the unit. Typically, with a brand new cartridge installed the pressure should be between 8 and 12. After usage of 2 to 8 weeks depending on the size of your filter check the pressure gauge again, if it’s up near 20 then it’s time to clean the cartridge.
Cleaning your cartridge with a garden hose or any other means will be sufficient for normal maintenance just to remove debris from the filter. After cleaning and reinserting the cartridge you should see the pressure gauge go back down to the 8 to 14 range. This indicates the filter cleaning was successful and your pool should again filter normally.
If during the filter maintenance process, you notice that after a cleaning the pressure gauge doesn’t drop back down to the 8 to 14 range or it does drop but then quickly rises back up in a matter of hours or days, then this indicates your pool filter cartridge has build ups such as: calcium, metals, algae, or oils that cannot be removed with standard cleaning.
Normally, this is an indication that it is time to purchase a new cartridge.
However, you can do the following filter cleanse to extend the life of your filter. Please note it is recommended to only do this to your cartridge filter once because of the harsh chemicals being used.
1. Find a bucket that is large enough to place your pool filter cartridge in so it can be submerged at least half way.
2. Fill the bucket with 20 parts water to 1 part pool muriatic acid.
3. Submerge your cartridge filter in the bucket.
4. You should see bubbling start to occur if there are any calcium or metal build ups in your filter (bubbling like hydrogen peroxide on a cut)
5. If you don’t see any bubbling, that just means there are no metals build up in your pool filter, but you can still have algae or oil build up, these will not bubble.
6. Let the filter soak for approximately 2-3 minutes. Then flip the filter upside down to soak the other half. Allow to soak for another 2-3 minutes.
7. Rinse off the filter thoroughly to remove as much of the chemical solution and debris as possible.
8. Reinsert directly back into your pool filter system.
9. Observe the pressure gauge reading. If it dropped back down to the 8 to 14 range and stayed down for at least a day, you have just successfully extended the life of your pool filter cartridge.
10. If there is no improvement, then your pool filter must be replaced pool maintenance.