Hello all this is my third year having my pool and I have never had this issue. Opened my pool this year and just last week had it in good shape. After shocking and killing all the algae pool was cloudy but clear in the shallow end. Well, I had an issue with my pump and i had it off for maybe 2 days. Pool started to turn green so I thought I was getting algae. I was able to get my pump up and running had no chlorine. I adjust my Ph to 7.3 and brought my pool up to shock level. It remained there until morning and no rise in my pressure. I thought was odd but decided to let it come down and try it again, same thing. I also did a deep cleanse on my filter I had this and I was pulling clumps of this cotton like stuff that his been falling like crazy. I thought that may have been preventing my filter from filtering correctly. For the last three night I have passed the OCLT with .5CC so I am thinking this isn't algae.
I can brush the stuff around it just sits on the bottom of my pool. Yesterday I vacuumed to waste, stuck a nylon on my skimmer basket. I have read on the forums of people having similar things and was able to make a difference by using skimmer socls and DE in their sand filters. I plan on getting some skimmer socks and some DE. Do you guys have any other suggestions?