Check whether the spa filter is done

How long they actually last Caldera says genuine filters last two to three years if you have kept up with cleaning. Bullfrog gives one to two years for cylindrical cartridges, and a much shorter twelve to sixteen weeks for the flat Simplicity filters. Check your own spa's documentation for which family you have. ## Signs it is finished early - Discolouration that survives a clean — brown, grey, green, or a stubborn dark yellow - Pleats permanently flattened - Fibres shredding - A cracked or split canister Any one of those and it is done, regardless of age.