Good morning. I've had the pool covered and running 5 hours per day for the last month. While I have been waiting for the water to drop below 60 degrees in order to close the FC level has been really consistent...was going down about 0.5 every 3-4 days while the water was warmer. During the last month, the only number I've had issue with is the pH which seems to continue to rise and level off at about 7.6/7.8 at which point I bring it down to 7.4 which is where I believe I want to be for closing. Well, with the last few days cool weather (26 degrees this morning...so left pump running overnight) my water is at 55 degrees and I'd like to close this week.
My numbers are:
FC = 6.5
CYA = 30
pH = 7.6
TA = 100
CH = 400
1) Do I just bring the pH down to a low 7.4-ish and call it a day and close?
2) I'm at 6.5 FC (about half of shock level) so once I take my water level down, I will add polyquat and continue to re-circulate for several hours. Do I check FC level again before closing and raise it above the 6/6.5?