So, once again, my CYA disappeared over the winter. That's a separate discussion. And the pool company that opened I don't think actually put any "shock" in because a couple of hours after they left my FC was at 0.5 and my CC was at 6.5. However, my TA is 80, CH is 60, and pH is 7.4. All great numbers. (My salt is only about 2000, so I need to get some salt too, but not a big deal either).
That being said, I need to shock this thing obviously (it's pretty green). With no CYA, what level should I bring it up to? For SWG pools, the shock chart only goes down to 60 CYA.
On a side note, is it possible they *did* throw shock in (they had two bottles pool side, but I didn't see them put it in or exactly what it was) and it went down that low that quickly?