A cartridge filter is one of the easiest parts of your pool to neglect, mostly because it does its job quietly until it suddenly doesn’t. Reduced water flow, cloudy water, and a pump working harder than it should are usually the first signs that your cartridge needs attention. The good news is that cleaning it yourself is straightforward if you follow the right steps and know when to stop and call in help instead.
How Often Should You Clean It?
Most cartridge filters need a clean every 4 to 6 weeks during the swimming season, though this shifts depending on pool usage, surrounding trees, and how well your water chemistry is maintained. A pool that’s used heavily, sits under trees, or has been struggling with algae will need more frequent cleans. If you’re not sure where your pool sits on that scale, our pool maintenance guide covers the broader seasonal routine a cartridge clean fits into.
What You’ll Need?
- Garden hose with a standard nozzle
- A bucket or tub big enough to soak the cartridge
- A pool filter cleaner or degreaser (or a cup of dishwasher powder as a budget alternative)
- Rubber gloves
- A soft-bristle brush (optional, for stubborn debris)
Step-by-Step: Cleaning Your Cartridge Filter
1. Turn Off the Pump
Always switch off the pump and, if your system has one, close the valves leading to the filter housing before you open anything. This isn’t just good practice — opening a pressurised filter housing while the pump is running can cause the lid to blow off forcefully.
2. Relieve the Pressure and Open the Housing
Most cartridge filters have a small air relief valve on top — open this first to release any built-up pressure safely. Once the pressure gauge reads zero, undo the clamp or locking ring and lift the lid off.
3. Remove the Cartridge
Lift the cartridge element straight out. Take a photo of the orientation before you remove it if it’s your first time, so you know exactly how it sits back in.
4. Hose It Down
Rinse the cartridge from top to bottom with a standard garden hose, working the water into the pleats at an angle rather than straight on — this pushes trapped debris out rather than further in. Rotate the cartridge as you go so every pleat gets covered.
5. Soak It in Filter Cleaner
For a proper clean (not just a rinse), soak the cartridge in a bucket with a dedicated pool filter cleaner solution, or a cup of dishwasher powder in warm water, for several hours or overnight. This breaks down the oils, sunscreen, and body lotion residue that a hose alone won’t shift, and is especially important if you’ve noticed a musty smell or your water’s been cloudy despite normal chemical levels.
6. Rinse Again and Inspect
After soaking, hose the cartridge down once more to clear the cleaning solution. While it’s out, check the pleats for tears, thinning, or a cartridge that’s gone rigid and brittle — these are signs it needs replacing rather than just cleaning. A cartridge typically lasts 2 to 3 years with regular care.
7. Reassemble and Restart
Slot the cartridge back in the same orientation it came out, check the O-ring seal for grit or damage, close the housing, and reopen the valves before switching the pump back on. Keep an eye on the pressure gauge over the next few days — a properly cleaned filter should bring your system pressure back down to normal.
Signs Your Filter Needs More Than a Clean
If you’re cleaning your cartridge on schedule but still seeing cloudy water, a struggling pump, or pressure that climbs quickly again within days, the issue may not be the filter itself. It’s worth having your pool equipment checked, since a failing pump or a cracked housing seal can mimic the same symptoms as a dirty cartridge and won’t improve no matter how thoroughly you clean it.
If cleaning genuinely isn’t cutting it anymore, or the pleats are damaged beyond repair, our sand and filter changes service covers replacing the cartridge (or converting to a different filter type entirely) properly and safely.
Don’t Forget the Water Chemistry
A clean filter works best alongside balanced water — if your chemical levels have drifted while the filter was clogged, cleaning the cartridge alone won’t clear cloudy water on its own. It’s worth getting your levels checked through pool water testing once the filter’s back in place, so you’re not chasing cloudiness that’s actually a chemistry issue.
When to Call in the Professionals?
Cartridge cleaning is one of the more manageable DIY pool jobs, but if your pool has slipped into green or heavily neglected territory, a filter clean alone won’t fix it — the filter will just keep clogging as fast as you clean it. In that case, our green pool recovery service tackles the underlying problem first, so your newly cleaned filter actually gets a chance to do its job.
If DIY filter maintenance isn’t something you want to keep on top of, we also offer full pool filter cleaning as part of our regular service, so it’s simply handled on schedule without you needing to remember.
Get Help If You’d Rather Not DIY It
Cleaning a cartridge filter isn’t complicated, but it’s one more thing on the list of pool upkeep tasks, and it’s easy to let the schedule slip. If you’d rather have it looked after properly and consistently, get in touch with The One Pool Care and we’ll take it off your hands.
Conclusion
A clean cartridge filter is one of the simplest ways to keep your pool water clear, protect your pump from unnecessary strain, and get the full lifespan out of your equipment. A regular clean every 4 to 6 weeks, done carefully and paired with balanced water chemistry, will handle most of what your pool throws at it.
But if the pressure keeps climbing straight back up, the cartridge looks worn out, or the whole job just isn’t something you want to keep track of, that’s exactly the kind of maintenance The One Pool Care handles as part of our regular service — so your filter stays clean, your water stays clear, and it’s one less thing on your list.
