Backwash the System

• Backwashing a diatomaceous earth system can resolve many of the issues. If a backwash doesn't work, it is time to start looking at other troubleshooting methods. A DE filter needs to be regularly backwashed on a specific schedule, usually every 3 to 4 weeks. If the filter needs to be backwashed more often to stay clean, the filter needs to be replaced. Before backwashing the system, empty the skimmers and the pump trap. The pump needs to be shut off to empty the trap. With the pump off, turn the valve to backwash, then turn the pump on until the water runs clear. Turn the pump off again and turn the backwash valve to filter or rinse if the valve is a multiport. Use the manufacturer recommendations for the number of times to run this sequence. When the number of sequences is complete, put the backwash valve back into the filter position and turn the pump back on. If the system is still running poorly, it is time to begin troubleshooting.
  
  

Crushed Filter or Manifold

• If the DE filter or the manifold is crushed, check the filter pressure. Backwashing the system on its regular schedule will lower the pressure buildup. You can also change the pump to one with less pressure. Another fix is to purchase a DE filter that is resistant to higher pressure.
  
  

Water in the Pool Is Not Clear

• If the water in the pool is not clear, do a chemistry test on the pool water. Check the DE filter to see if it is dirty. Replace with new DE medium. It may be that the pool is being used heavily; increasing the run time on the pump will help. Low water flow will also keep the water dirty looking. Check the level of the pool water and increase, if necessary. Look for debris in the lines and closed valves. Clean the skimmer and skimmer basket.
  
  

DE Powder in the Pool

• If you see diatomaceous powder in the pool, check the DE filter for damage. Look at the filter grids for holes. Check the filter neck to ensure it fits tightly in the manifold. Inspect the manifold for cracks. Make sure the strainer in the filter system is there and not broken. If there are no problems with the DE filter, check the backwash valve to see if the filter medium is bypassing the filter.