When (and How) to Clean Your Cartridge Filter

The pressure gauge on your filter is the most underrated piece of equipment in your backyard. It tells you almost everything you need to know.

Write down the pressure right after you've cleaned or backwashed the filter. That's your clean baseline. For most home filters in Florida it's between 8 and 14 psi.

When that pressure climbs 8–10 psi above baseline, the filter is asking for attention. Sand filter? Backwash for 2 minutes, then rinse for 30 seconds. Cartridge filter? Pull the cartridges and rinse with a garden hose. DE filter? Backwash and recharge.

Once a year, do a deep clean. Cartridges should soak overnight in a filter cleaner solution (or a 10% muriatic acid bath if there's heavy calcium scale). Sand should be replaced every 5–7 years.

When to replace the cartridge entirely: when it has visible tears, when the pleats are matted flat, or when even after a deep soak the clean pressure doesn't return to baseline. Usually 2–3 years in Florida.