Domakihub How to Clean a Hot Tub Filter and Keep Your Water Pristine
A simple, step-by-step routine that extends filter life and protects every soak.
Reviewed by Domakihub pool pros · 2026-06-23 · 5 min read
A dirty hot tub filter is the fastest route to cloudy water, strained pumps, and expensive repair bills — especially in Greece, where summer heat and heavy holiday-rental use push filters to their limits far faster than in a temperate climate. The video above walks through the cleaning process visually, while this guide gives you the exact steps, schedules, and product tips you need to stay on top of it. Whether you manage a private villa in Mykonos, a hotel rooftop tub, or a home installation in Athens, a clean filter is the single highest-leverage maintenance task you can do.
Why Hot Tub Filters Need Regular Attention
Hot tub filters trap everything that enters the water — sunscreen, body oils, hair, dust, and the mineral-rich particles common in Greek tap water. Over time these contaminants clog the polyester pleats, forcing the circulation pump to work harder, reducing heat efficiency, and allowing bacteria to thrive in stagnant pockets of the filter cartridge.
A neglected filter does not just look bad; it shifts the chemical balance of your water. Sanitiser such as chlorine or bromine is consumed faster trying to compensate for what the filter is failing to capture, meaning you spend more on chemicals for worse results. Staying on top of filter cleaning is ultimately the cheapest thing you can do for your hot tub.
How Often Should You Clean a Hot Tub Filter in Greece?
For lightly used residential tubs, a quick rinse every two weeks and a chemical soak every four to six weeks is a reasonable baseline. For holiday-rental villas or hotel spa facilities that see multiple bathers per day in peak season (May through October), rinse the filter weekly and perform a chemical soak every two to three weeks without exception.
Most cartridge filters last 12 to 18 months before the pleats degrade enough to warrant replacement. Keeping a spare cartridge on hand lets you rotate filters — soak one overnight while the tub runs with the other — a trick that adds months of life to both cartridges and removes any excuse for skipping the deep-clean cycle.
5 Steps to Clean a Hot Tub Filter
- 1
Power down and remove the filter
Switch off the hot tub at the breaker or control panel before opening the filter compartment. Most cartridge filters unscrew or unclip from a standpipe inside the skimmer or equipment bay. Lift it out carefully — a saturated filter is heavier than it looks — and carry it to a flat area where you can work with a hose.
- 2
Rinse out loose debris with a hose
Hold the cartridge at a 45-degree angle and use a firm but not jet-pressure stream of water, working your way from top to bottom along each pleat. Rotate the cartridge a quarter-turn after each pass so you cover all four sides. This removes the bulk of surface debris — hair, leaves, visible grit — in a couple of minutes. Never use a pressure washer; the force tears the polyester pleats and ruins the filter.
- 3
Soak in a filter-cleaning solution
Fill a bucket or dedicated filter-soak container with cold water and dilute a filter cleaning or degreaser product to the concentration on the label. Submerge the cartridge completely. Allow it to soak for at least one hour for a routine clean, or overnight (eight to twelve hours) for a deep clean following heavy use or a water change. The soak breaks down oils, scale, and biofilm that rinsing alone cannot remove.
- 4
Rinse thoroughly and inspect the pleats
After soaking, rinse the cartridge again with the hose until the water running off is clear and produces no foam. Any residual cleaning chemical entering the tub will spike foam and throw off your pH. While rinsing, inspect each pleat: look for tears, collapsed folds, grey or brown staining that does not wash out, or a persistent musty smell. Any of these signs indicates the cartridge needs replacing, not just cleaning.
- 5
Reinstall and rebalance the water
Slide or screw the clean, fully rinsed cartridge back into its housing, making sure any O-rings are seated correctly. Restore power, let the pump circulate for 15 to 20 minutes, then test the water chemistry and adjust pH (target 7.2–7.6), alkalinity, and sanitiser to their correct ranges. A clean filter circulates water more efficiently, so you may need slightly less sanitiser than before.
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FAQ
- Can I put my hot tub filter in the dishwasher?
- It is a popular hack, but it is not recommended. Dishwasher detergents contain foaming agents and enzymes that are very difficult to rinse out completely, and the high heat of the drying cycle can warp and shrink the polyester pleats, shortening the filter's life. A proper filter-cleaning soak costs very little and does a better job without the risk.
- How do I know when a hot tub filter needs to be replaced rather than cleaned?
- Replace the cartridge if the pleats are visibly torn, crushed, or fraying at the top and bottom caps; if the fabric has turned a permanent grey or brown even after a full overnight chemical soak; or if the filter is more than 18 months old and water clarity stays poor despite correct chemistry. A degraded filter passes contaminants rather than capturing them.
- Is it safe to use bleach to clean a hot tub filter?
- Household bleach (sodium hypochlorite) will disinfect the filter but it is too harsh for regular use — it degrades the polyester fabric quickly and leaves a chlorine residue that is hard to rinse fully. Purpose-made filter cleaning solutions are formulated to dissolve oils and scale without attacking the material, and they are inexpensive enough that there is little reason to use bleach as a substitute.