With DE, is it always about 80% each time you backwash?

[Jason B]

First, let me WELCOME you to TFP

Getting all the De out of a filter is impossible, unless you break it down and thoroughly hose the grids/ fingers. A complete backwashing (i.e. backwash/ rinse, backwash/ rinse ... until the water runs ~ clear on backwash) will still only remove ~ 80% of the DE. As such, you should only add 80% of the recommended De when recharging the unit (if the unit takes 6 lbs clean, only add 5 lbs after a backwash) You probably saw the result of adding the full amount of DE after a number of incomplete backwashes, a LOT of extra De in the filter - which prevents the unit from functioning correctly/ efficiently.

I have a Hayward De E65a filter, which takes 6 lbs of DE. You said after a backwash only add 5 lbs since only 80% is removed. I'm about to backwash for the "2nd" times this season. Does that mean after I backwash that only 60% will come out, and I should only add 4 lbs in? Or is it always about 80% each time you backwash?

 

[Jason B]

Re: ~20% of DE Remains in Filter after Six Months?

bump

 

[FamilyGuy]

Re: ~20% of DE Remains in Filter after Six Months?

It removes about 80% every time you backwash so add the full 6lbs the first time after filter breakdown then only add 5lbs after the subsequent backwashes