I cannot, for the life of me, get an accurate test for CYA. 10k gallons, vinyl, above-ground. Last year when I bought my kit, the CYA test did not register after multiple tries. I added CYA (I forget exactly how much, enough to get it to 40, via sock).Tested sometime later, no reading. So I went ahead and added the same amount again, via sock. I eventually got my pool cleared up and basically just maintained my FC between 4-8 even though I had no real clue what my CYA was at.
Fast forward to now. I'm starting to open the pool for the summer. It was green. I still cannot get an accurate reading for CYA. I can tell you that I somewhat haphazardly added 12.5% to the pool for the passed week. I was basically trying to keep the FC "high" (around 20). There were times when I would have it so high that I stopped adding drops of 871. I would test later or the next morning only to have the FC around 6ppm or less. CC has been anywhere from .5 up to 3.
My most recent test, this AM had the FC very high (again, I haphazardly added 4 gallons last night, because the FC seeemd to be going pretty quick). This AM my tests were as follows:
FC: 33, CC: 3, PH: 8, TA: 90
The PH is high this AM, but I've been keeping it down around 7-7.2 with muratic acid. It will drop for a day or so only to come back up. I added some more muratic acid this morning but nothing else. I will re-test everything again around lunch time if I can get home.
I wish I had a better idea of what my CYA level actually was. I can't believe that it's actually ZERO since I added some much stabilizer last season.
I also seem to have some SAND in the pool. I'm guessing it's play sand from the kids but I'm not sure. I can't seem to get it off the walls with a standard brush. I pulled the stairs out of the water and there's quite a bit of sand on them.
I've backwashed the filter (but need to get a new guage because the current one isn't reading at all). The glass jar looks clear. I may replace the sand in the filter anyway, as it's been several years or more. I haven't officially swept the pool but I've brushed it daily and gotten most of the dead leaves out I believe. I will sweep it this evening if possible.
Sorry for the long windedness. The next one will be a lot shorter, with just test results. I promise!