When should you replace a hot tub filter?

A filter wears out even when it is looked after. The fabric loosens with every cleaning, and after enough months it stops catching fine dirt no matter how clean it looks.

Signs a filter is done

• It stays gray or brown after a proper clean and soak.
• The pleats are flat, fuzzy or frayed, or the fabric has a tear.
• The end caps are cracked or the core has softened.
• The water goes cloudy sooner than it used to after a clean.

What changes how long one lasts

• How much the tub is used. More soakers means more to catch.
• How it is cleaned. Regular rinsing helps it last; harsh cleaners and pressure washers shorten its life.
• The maker's own figure. A few makers ask for a new filter more often than once a year. Your manual says which yours is.

Keeping a spare

With two filters you can swap in the clean, dry one on cleaning day and let the other dry fully before its next turn. Both last longer, and the tub is never waiting on a wet filter.

This is general guidance. Your hot tub's owner's manual comes first, and so do the instructions on your products.

Sources: Jacuzzi: Hot tub filter cleaning made easy; Hydropool: How often should I change my hot tub filter?.