How to Set Up a DE Filter in Your Pool

A pool with life preserver
  • 1-8 hours
  • Intermediate
  • 100-1,500

The DE filter received its patent in the early 1990s and has become one of the most popular types of pool filters, due to its ability to strain out particles smaller than 10 microns in swimming pool water. Some models of DE filters are nearly 10 times as effective in screening out particulate matter as conventional cartridge and sand filters. DE filter systems are available for use with both above-ground and in-ground pools at a cost comparable to large sand filters.

Step 1 - Prepare the Old Filter Pipe to Attach the DE filter

Detach the previous filter, leaving as much pipe intact as possible. Connect three male-shaped pipe adapters to the three female-shaped ports at the bottom of the new DE filter.

Ports should be clearly marked with their function, such as "In," "Backwash" and "Pool."

Step 2 - Establish the New DE Filter in its Permanent Position

Diatomaceous Earth

Direct the pump pipe to Filter Input. Direct the outlet pipe to return pipeline and the backwash/waste line to waste pipe. Scrub the connections clean before affixing permanently with waterproof glue.

Step 3 - Check the Pump

Once the DE filter is fully connected, test it with the pool pump. Turn the pump on and inspect to see that it is operating properly. Check for a filter gauge pressure of 12 to 16 pounds per square inch based on the pump capacity.

Step 4 - Apply a Layer of DE Powder to the Rods in the Filter

Add a one-lb. can of DE to the filter unit for every 10 square feet of filter area. For 36 square feet, you would add four cans of DE powder.

The DE is continuously applied in a slurry format to the filter rods by a body feed system to keep it evenly coated.

Maintaining the correct rate of water flow through your filter, approximately one to 1.5 cubic feet per minute for each square foot of the filter. This will also help coat the DE filter rods.

Add a one-lb. can of DE directly to the gutters and skimmer of your in-ground pool every morning to coat the filter rods properly. Keep the loose DE powder out of the main pool area. For above-ground pools, add the DE to the skimmer intake.

Step 5 - Clean the Filter Elements and Rods Monthly

aerial view of a swimming pool

Rust, iron, calcium, and other minerals rapidly build up on the DE filter rods, so remove and clean them monthly according to the procedure in the owner's manual. Clean upon noting a rise of eight lbs. in the normal pressure, and after any power outage, using filter cleaning chemicals.

Step 6 - Replace the DE Filter Grid Every Two to Five Years

Take the DE filter grid and your owner's manual with you when purchasing a replacement to ensure the new one will function properly in your pool filtration system.