Topic:  Cartridge Cleaning Instructions from Unicel

Source:  Unicel – a leading cartridge manufacturer

When should a cartridge element be cleaned?

For swimming pools, clean the cartridge when filter canister pressure reaches 8 PSI above the initial system or new cartridge starting pressure. For spas, establish a routine cartridge cleaning schedule based on the amount of spa usage. If Baquacil is used as a sanitizer, the filter element must be cleaned with Baqua Clean before any cartridge cleaner is used (Step 4). Please refer to “Cartridge Cleaning for Baquacil Users.”

What is the procedure to clean my cartridge?

1. Remove the cartridge from the filter housing following the manufacturer’s instructions.

2. Use a garden hose with a straight flow nozzle to wash down the filter element. Work from the top down, holding the nozzle at a 45 degree angle, and wash all the pleats with emphasis between pleats.

3. Rinse until all dirt and debris is gone.

4. For all spa cartridges and elements used in swimming pools where perspiration, suntan lotions, and other oils are present, soak the element for at least one hour (over night is most effective) in (1) a commercial filter cleaner; or (2) one cup trisodium phosphate (TSP) to five gallons water; or (3) one cup dishwasher detergent to five gallons of water.

5. Rinse the cartridge again to remove oils and cleaning solution.

6. If the filter has a coating of algae, calcium carbonate (residue from calcium hypochlorite), iron, or other minerals, soak the cartridge in a solution of one part muriatic acid to twenty parts water until all bubbling stops. Click here to learn more about Acid Washing.

WARNING: Failure to remove all oils and cleaning solution before acid soaking will result in a permanent restriction of water flow and cause premature cartridge failure.

7. Rinse the cartridge clean and reassemble housing.

WARINNG: Wear rubber gloves and safety glasses when using acid and chlorine. Do not add water to acid. Do not mix chlorine and acid.

NOTE: Most manufacturers do not recommend the use of diatomaceous earth (DE) with cartridge filters. DE particles will become trapped in the body of the media and shorten cartridge life. If desired, a cellulose fiber (synthetic DE) can be used in moderation.