Your pool filter cartridge tells you when it's done.

Yes, the pressure gauge is the main clue, but there’s more to it.

After you clean the cartridge, note the clean pressure. Once the pressure climbs 8-10 psi above that, the cartridge is clogged beyond cleaning — it’s done. A cleanable cartridge should go back to near its original pressure. If it doesn’t, the media is worn out.

Visually, you’ll see tears, frayed ends, or the pleats feel stiff and brittle instead of flexible. If the material is falling apart, replace it. Also, if your pool stays cloudy even after a fresh chemical balance and a clean cartridge, it’s not filtering properly.

Don’t wait until you’re running the pump longer to get the same flow. A blown-out cartridge risks sending debris back to the pool or wearing out your pump.

A new cartridge costs less than a new pump.