How a D.E. Filter Works

Diatomaceous earth is a porous powder with microscopic openings that when magnified look like tiny sponges. Clear water can pass through these openings, but particles, as small as two to five microns, are trapped during the first pass through the media. D.E. filters have internal elements that become coated with D.E. It is this ‘filter cake’ that strains dirt, dust and algae from the water.

Diatomaceous Earth

Similar to sand filters, when D.E. filters become dirty, they are cleaned by regenerating and draining the clogged D.E. to the ‘waste’ line. To restore filtration, a fresh ‘charge’ of D.E. is added to the filter.

Perflex® Extended-Cycle Filters

Hayward D.E. Filter

EC75A Series

  • Exclusive bump handle activates the mechanism causing the Flex-Tubes to instantly and uniformly clean themselves of dirt and filter powder
  • Self-venting design automatically expels any air that may be present in the system
  • Proven, patented Flex-Tube filter elements efficiently reuse the filter powder and dirt mixture forming a fresh filtering surface
  • Combination pressure gauge and threaded inspection/service port is easy to read and remove when filter needs cleaning
  • Heavy-duty filter tank injection-molded of high-strength for dependable, corrosion-free performance
  • Integral check valve prevents system backflow whenever pump is off

Downloads

How to Start and Maintain a Diatomaceous Earth Filter

  • Scoop 7lbs (3.2kgs) of Diatomite into the filtration system through the pool’s skimmer as fast as the plumbing will take it. Note and record the reading on the pressure gauge after the Diatomite has been added. This is the Precoat Pressure.

  • Filtration starts immediately after the filter has been precoated. As the filter works to remove dirt from the pool water the accumulation of dirt will cause a resistance to flow. This will cause the pressure gauge to rise and flow will decrease. When the pressure rises 7-10psi above the precoat pressure regenerate the filter.

  • Stop the pump. Move the bump handle down slowly then up briskly. Repeat this 3 times.
  • Restart the pump and filtration will resume near the original flow and pressure.
  • After each regeneration and until the filter is cleaned there may be a slight increase in the starting pressure. This is completely normal and is the result of dirt accumulating inside the filter.

  • When the gauge pressure rises more than 10 PSI in less than 24 hours OR when cloudy water returns into the pool for more than 30 seconds after regeneration, it is time to clean. 
  • Stop the pump and move the bump handle down slowly, then up briskly. Repeat this 8 times. 
  • Open the vent valve located under the bump cover, open the filter drain and allow water and dirt to empty completely. (*Note: If filter is installed below pool water line, close suction and return valves)
  • Once the filter has drained run the pump with the drain still open for a few seconds to flush out any remaining dirt at the bottom of the filter. (*Note: If the filter is installed below pool water line, opening suction valve for a few seconds with the pump off will adequately flush the unit)
  • Close the filter drain and the vent valve.
  • Open the suction and return valves.
  • Start the pump and let the filter fill with water and repeat the cleaning procedure

  • After the cleaning process repeat the precoating step listed above.

  • For fastest results regenerate the filter before and after each vacuum.