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Choosing the Right Hot Tub Filter Cartridge

A filter cartridge that fits badly or is worn out lets debris through and strains your pump. Here is how to pick the right one.

By Oldyon Team1 min read

Rinsing a pleated hot tub filter cartridge with a garden hose

Hot tub filters look similar but are not interchangeable. The wrong size either bypasses water around the cartridge or restricts flow until the pump struggles and the heater trips.

Match the dimensions

Measure the length and outside diameter of the cartridge you are replacing, and note the thread or end-cap style. Cross-check those against the part number printed on the old filter before ordering.

Rinse weekly, replace yearly

Rinse the cartridge with a hose every week and soak it in filter cleaner monthly. Even well-kept cartridges lose pleats over time, so plan to replace them about once a year, or sooner in heavily used tubs.

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The parts these guides talk about

Filter cartridges, jets, pumps and seals, in the Oldyon Spa Shop. Search by part name or by the code on your old part.

Visit the shop
Hot tub parts laid out on a deck: a filter cartridge, jets, a pump, O-rings, a headrest pillow and a control panel.