How to clean inflatable hot tub filters

Why the filter matters

On most inflatable tubs, the pump draws water through the filter before it passes the heater. A clean filter keeps flow steady, which the heater needs to work safely. A clogged filter lowers flow, which can trigger a flow error, such as E02 on many Lay-Z-Spa pumps, or stop heating without a code.

Filters also hold the debris that sanitiser breaks down. If they are dirty, sanitiser is used up faster and problems like cloudy water and biofilm follow.

How to rinse a filter

Use a normal hose spray rather than a pressure washer, which can damage the fibres. A dedicated filter wand helps reach between pleats.

1. 1

   Switch off and unplug the pump.

2. 2

   Open the filter housing as the manual describes and lift out the cartridge.

3. 3

   Hold it at an angle and rinse with a garden hose, working down each pleat from top to bottom.

4. 4

   Turn it and repeat until the water runs clear and the pleats look clean.

5. 5

   Check for tears, crushed pleats or a split end cap.

6. 6

   Refit the cartridge, close the housing and restart the pump.

Soaking and deep cleaning

Rinsing removes loose debris, but oils and scale stick to the fibres. Every week or two in regular use, soak the cartridge in a hot tub filter cleaner, as the label directs, then rinse thoroughly. In hard water areas, scale can make the filter feel stiff; a cleaner that tackles scale helps, as general guidance.

Many owners keep two cartridges, so one can soak and dry while the other is in use. A filter that dries fully between uses also resists slime.

Note:Wear gloves when using filter cleaners, follow the chemical maker's instructions and rinse thoroughly so no cleaner goes back into the tub. Never use household detergent or dishwasher cleaning on filters.

How often to clean and replace

Paper cartridges in small inflatable pumps wear out faster than large pleated filters in hard shell tubs. Keep spares, especially in summer.

Finding the right filter

Filters are model specific. Bestway uses type codes such as type VI, which the Santorini listing names, and other types for different pumps. Intex, MSpa and Wave have their own sizes. Check the manual or the label on the old cartridge for the type, and compare the height, diameter and end fittings before buying.

Some tubs accept reusable foam or washable filters as alternatives. Use only filters that the maker or the filter seller says fit your model, as a poor fit lets water bypass the filter.

Compare Lay-Z-Spa models →

Common filter problems

Most water problems improve when the filter is clean. See cloudy water for the checks in order.

• Flow error straight after cleaning: check the cartridge is seated and the housing closed.
• Filter clogs in a day: water may be very dirty; shock and consider a drain and refill.
• Crusty, hard cartridge: scale; soak in cleaner or replace, and check pH.
• Slimy cartridge: biofilm; replace it and purge the lines. See slimy hot tub.

Storing spare filters

Keep spare cartridges dry, in their wrapping and out of direct sun until you need them. A used cartridge that you plan to reuse should be cleaned, rinsed and dried fully before storage, or it can grow mould. At the end of the season, many owners simply fit a new filter when the tub goes back up in spring.

Frequently asked questions

How often should I clean my Lay-Z-Spa filter? Rinse it every few days when the tub is in use and replace it when it no longer cleans up.

Can I put hot tub filters in the dishwasher? No. Use a hose and a filter cleaner made for hot tubs.

Do CleverSpa or Intex tubs use Lay-Z-Spa filters? Not as a rule. Use the type in your manual.

Can I run the tub without a filter? Do not, unless the manual says so for a specific step. The filter protects the pump and heater.