I had my above ground pool opened last Saturday. I am running a Hayward perflex ec50. Since opening and trying to clear my pool up, I have noticed I have had to do a lot of back washing to make sure the return pressure stays up. The PSI increases quickly. I have also took it apart and hosed off the fingers. It will run ok for about 1-2 hours before having to bump. Then maybe 24-48 hrs before a backwash seems necessary. I have been using Aqua perl as past owner left bags of it following back washing. Is this normal? Can all of the chemicals I'm using to clear up my pool be causing this? I have noticed when I open drain to backwash and when I cleaned the fingers there was a lot of yellow built up/clumps of DE (what I believe to be the DE). Any help would be appreciated!