How Often Should a Pool Filter Be Cleaned?
Ask ten pool owners and you will hear ten intervals. The correct answer is not an interval at all — it is a pressure reading measured against your filter's clean starting pressure.
Find Your Clean Pressure
Immediately after a proper cleaning, with the pump at its normal operating speed, note the gauge reading. That number is your baseline, and it is specific to your pool, your plumbing and your pump speed. Write it on the filter with a marker if that helps.
When the gauge climbs roughly 8 to 10 PSI above that baseline, flow has fallen enough that the filter needs service. Without the baseline, a reading of 20 PSI means nothing — it might be perfectly clean or badly clogged depending on the system.
Typical Intervals in Bakersfield
- Residential cartridge filters: often every 3 to 6 months
- DE filters: backwash as pressure indicates, full grid cleaning periodically
- Sand filters: backwash on pressure rise, media replacement every several years
- After a green pool recovery: sometimes several cleanings within a couple of weeks
- Dust season and heavy wind events: sooner than you expect
Cleaning vs. Replacing
If pressure returns to high within two or three weeks of a thorough cleaning, the media is finished, not dirty. Flattened pleats, fraying fabric, broken end caps, calcified surfaces and channeled sand all mean replacement. Continuing to clean worn media costs you flow, clarity and pump life.
Why It Matters Beyond Clarity
A restricted filter makes the pump work harder and run hotter, reduces turnover so chemicals distribute unevenly, and can prevent a heater from reaching its required flow. Filter neglect shows up as equipment failures long before it shows up as cloudy water.