Hi! Long-time browser who finally wised up and joined this awesome website!
I bought my house a year ago. Never owned a pool before, but the previous owner said it wasn't very difficult to maintain the pool and hot tub. HA! I've had nothing but trouble with both.
My current problem, which I was mystified about until I came here, is that I keep getting "crud" -- a fine, powdery accumulation on the bottom of the pool that brushes up easily into a cloud. Sometimes it's gray, sometimes light brown, sometimes a light green. We had problems at the beginning of the season with maintaining the FC levels, and ended up dumping 11 pounds of shock over 24 hours (6 in the evening and 5 the next morning) on the advice of the pool store guy. That seemed to do the trick, but the crud still appears regularly. I'm brushing the pool every day at this point, and it comes back as bad or worse within 24 hours.
After reading the Pool School article, I suspected my CYA was too high. Sure enough, it tested out at around 90 or 100. So it looks like the crud is probably dead algae? I haven't seen any live algae, save for a small spot in the skimmer door early in the summer, which hasn't grown back after we scrubbed it off and added algaecide.
FYI, the pH is currently at 7.6, the Cl is at 5.0 (we shocked 5 days ago), and the TA is around 80.
The water is usually crystal clear, but becomes a little cloudy after brushing up the crud.
I plan to dump some of the water and refill this weekend to get the CYA level down. Any idea how much water I need to dump? Half the pool? Less? More?
Oh, also, the liner is tinted pale green in spots -- mostly along the underwater rim around the deep end. I'm guessing this is from the copper in the algaecide, as it is definitely not algae and doesn't scrub off. Any idea how to get rid of it?
Thanks in advance for your help. This site is awesome, and my just save my sanity! Not to mention my wallet!