Split by moderator from HERE. Please start your own thread to ask your own questions ... it will be less confusing and you will get personalized responses. Thanks, jblizzle
Just curious - is shocking really necessary before closing or is it more of just in case recommendation?
I've had 0 issues since I started using Clorox he 8.25%. Interestingly, I've had days (sunny, low 90s) when 24hr FC loss was under 1ppm. (I didn't really have issues with Austin Chlorine either, but like Clorox better - more predictable. I think Austin may not always been 12.5%)
For the last of couple weeks I didn't test my water, knowing that 64oz of 8.25% adds 2 and raises FC back to 5. (cya 30-40. 22k). Today I tested it and it's 7.5-8. If I had to guess I probably had it above 5 for a couple of weeks now, since the water dropped to 70.
The reason I'm asking this - I want to close my pool this week and I want my FC be around 3 when I put the cover on, but I am not sure if it'll drop from 16 to 3 within 3-4 days. (solid cover manufactures recommend minimum chlorine level, if any). I can't say I'm a big fan of polyquat, used it last closing and had CYA <10 when I opened this spring, but I bought 1 gallon bottle, so I may as well use it