How often should I have to backwash my DE filter when opening a dirty pool?

[Mddan2474]

Hello all,

I am struggling with a filtration issue.
I have a 32000 gallon pool with Pentair FNS 60 DE filter and Pentair variable speed pump and saltwater chlorine generator. This was all purchased in beginning of 2021, so 3 summers of high use in the northeast US.

Every year when I open the pool it is very dirty. We have semi permeable cover with lots of overhanging trees. This year the filter was requiring backwashing every hour, as indicated by pressure gauge and low flow indicator on chlorine generator.

After a couple of days I decided to pull apart filter for cleaning and throughly rinsed the grids, etc. I had done this towards the end of last season as well. I didn’t see any cracks in the manifold or any tears in the filter grids. I put it all back together and it worked beautifully…for about 12 hours? Now it is indicating low flow and increased pressure and I am feeling super frustrated.

The pool is cleaner than it was upon removing the cover but still very dirty. Do I just keep backwashing and adding more DE every time? Are there any tricks or suggestions for cleaning a very dirty pool with a DE filter?

 

[ajw22]

The filter is doing its job.

Do you have a pool cleaner running in the pool?

I hire a pool service to do an initial vacuum of the pool after opening with their standalone rig to clean the pool. I also have a solid cover that lets less debris into the pool over the winter.

This is how my pool looked on opening this year before any cleaning…

 

[Mddan2474]

Yeah mine was way worse. I think the permeable cover with the amount of trees and nature around the pool was a mistake. Maybe the pool service stand alone vacuum is an idea.