Filtration & Circulation /
How Often Do You Change an Above Ground Pool Filter Cartridge?
Most above ground pool filter cartridges are not replaced on a fixed calendar. Clean them regularly, then replace the cartridge when cleaning no longer restores flow or damage appears.
Archive date: this article was written for PoolSkimmer on Oct 24, 2026 and given the earlier archive date of Nov 15, 2025 so the blog reads as an organized archive. It was not published on that date.
Filter cartridge: when to change it
There is no need to adhere to a rigid weekly or monthly timetable for replacing an above ground pool filter cartridge. A more practical approach is to make regular inspections, give it a clean whenever debris impedes the flow, and put in a new one only when cleaning is of no further use or the manufacturer deems it necessary.
The difference between a clean and a replacement
The job of your cartridge filter is to let water circulate while holding back dirt and other matter. Eventually the pleats will be full and the unit may appear soiled even after you have rinsed it, but that is not necessarily an indication it has to be discarded.
You should replace the cartridge under these circumstances:
- You see torn, frayed or otherwise distorted pleats
- Rinsing and cleaning do not clear a clog
- There are no visible blockages yet the water flow is still weak
- More debris is making it through than usual
- The service-life limit or interval set out in the manual has been reached
Telling signs it is time for some work
When the circulation system does not perform as it should, the filter requires your attention. You will know this from a few common indicators:
1. The return flow to the pool is down 2. Pressure on the filter is running higher than normal 3. The cartridge is clogged once more in short order 4. Despite the circulation being on, the water remains cloudy
If your equipment has a pressure gauge, check the psi against what a clean reading looks like; a marked increase means it is time to clean the cartridge. Should the flow and pressure fail to come back up, the cartridge could be at the end of its run or there is another issue with the pool gear.
Inspection frequency
During the swimming season it makes sense to get into the habit of a weekly check. Do not put it off until the filter fails entirely.
An effective maintenance plan would be to inspect the cartridge each week and clean it as soon as you notice any restriction in the water. Make sure the skimmer basket is empty to keep the load on the filter down, and follow the book on when to replace. Of course, if you have heavy use, windy days or sunscreen residue, the pool will demand more frequent care. Some can go longer without a cleaning. There is no one size fits all rule for every three months.
What to avoid
Under no circumstances should you open the filter or put your hand in the skimmer basket with the pump running. Shut the pump off before you go near the cartridge or basket area. When servicing the equipment or handling dirty parts, put on the proper PPE and hearken to the chemical labels and the manual.
And do not jump to the conclusion that a cloudy pool means a new cartridge is in order. That symptom can just as easily be traced to poor chemistry, clogged plumbing, low circulation or a dirty skimmer.
Time to call in a professional?
A qualified pool pro should be contacted if the housing, seals or plumbing are damaged, or if the pressure gauge is giving inconsistent readings. If you cannot tell if the cartridge is the right type or is put in correctly, get an expert’s opinion. Likewise, if the thing clogs with unusual frequency, a professional can ascertain whether it is normal wear and tear or a fault in the system that needs to be fixed.
Sources and further reading
- [Hayward: Weekly pool maintenance](https://www.hayward.com/maintenance/weekly-pool-maintenance)