Applies To

All cartridge and DE filters

Question / Problem

How Do I Clean My Cartridge or Diatomaceous Earth (DE) Filters?

Safety Warning

Common Application / Operating Conditions

Clean the filter when the pressure gauge reads eight to 10 PSI above the initial start-up pressure. Always record the start-up pressure when installing or replacing a filter cartridge. Cleaning intervals are based on pressure, not operating time, and will vary depending on water conditions.

Step-by-Step Resolution

1. Prepare the System for Service

   Make sure the pool pump is off. Turn off all automatic controls and the circuit breaker. Close all suction and return shut-off valves.

2. Relieve Pressure and Drain the Filter Tank

   Open the air relief valve slowly to release system pressure. Remove the drain plug from the bottom of the tank and allow all water to drain out.

3. Remove the Filter Top and Cartridge

   Press the safety latch to release it from the locking ring. While holding the latch, turn the locking ring counterclockwise to remove it. Flush debris from inside the tank. Lift the cartridge straight up. If your model uses locking tabs, turn the cartridge to unlock it before lifting.

   Use caution to avoid damaging the flow diverter during removal.

4. Rinse the Cartridge

   Using a garden hose with a nozzle, rinse the cartridge thoroughly. Start at the top and work downward at a 45° angle. Clean all pleats and the spaces between them to remove dirt and debris.

5. Soak the Cartridge to Remove Oils

   If the cartridge becomes coated with oils or debris introduced by swimmers, soak it for at least one hour (overnight preferred) using one of these methods:

   • Commercial filter cleaner - follow the manufacturer’s instructions.
   • One cup (eight oz) trisodium phosphate (TSP) mixed with five gallons of water.
   • One cup (eight oz) dishwasher detergent mixed with five gallons of water.

   After soaking, rinse thoroughly. Inspect the cartridge for cleanliness and damage. Repeat cleaning if necessary. Replace the cartridge if damaged.

6. Remove Scale or Mineral Deposits

   If the cartridge is coated with algae, calcium, iron, or other minerals, soak it in a solution of one part muriatic acid to 20 parts water (six fl oz acid per gallon). Leave it in the solution until bubbling stops.

   Important: All oils must be removed before acid soaking. Acid applied to oily cartridges will permanently damage the media.

   Warning: Wear gloves, eye protection, and protective clothing. Always add acid to water - never water to acid.

   Rinse the cartridge thoroughly after the acid bath. Replace the cartridge if mineral removal no longer restores performance.

7. Reassemble the Filter Tank

   Install the drain plug, then place the cleaned cartridge into the tank base. Ensure the air bleed tube is properly installed. Clean the o-ring seat, inspect and position the o-ring, and apply a thin layer of silicone-based lubricant.

   Place the top assembly on the base and turn the locking ring counterclockwise until it drops into place. Rotate the top so the air relief valve faces away from electrical components. Turn the locking ring clockwise until the safety latch clicks into place.

8. Restart the System and Purge Air

   Open all shut-off valves. Turn the pool pump on while standing clear of the tank. When a steady stream of water flows from the air relief valve, close it by pushing down and turning clockwise two turns. Confirm there are no leaks and verify the pressure gauge returns close to the start-up value.

Tips / Additional Notes

• Always clean the cartridge when pressure rises eight to 10 PSI above the start-up pressure.
• Cleaning frequency depends on water quality, bather load, and environmental debris.
• Record start-up pressure when installing a new cartridge to establish a cleaning baseline.
• If you are not comfortable performing this maintenance, contact a qualified pool service professional.