Thanks! It is such a great relief to see blue water again. Maybe I'll be able to sleep better now! You have been a great help and a confidence booster for me. My granddaughter will be getting a nice tip, btw! Polyquat 60 is what I've always used, I genereally add 6 oz. a week as a preventative. I am planning on using my skimmer socks also. I hope this is my last post about this issue. But I will continue to read this forum periodically, because everything I do know about pool maintenance I have learned here over the last few years!! Just a quick comment, I went to Leslie's the other day to get another bottle of R=0871 (I was using so much of it, I thought I might run out) and they didn't have any. He asked me what it was used for and I told him you use it with the powder for a chlorine drop test. He says "Oh, the powder, well that's been discontinued because it is soooo very inaccurate! You need to stop using that!" I just said "I guess I don't have any business being here then." And I walked out! He must be an idiot, because how else would I measure these high FC levels?? Before I discovered Pool Solutions, I would have believed and trusted him. HA!