Posted below, but no one responded. If anyone can just respond briefly, I'd appreciate it.

Have 22,5k gallon IG, plaster, SWG. Have mustard bloom. Raised ch to 15 for a few days, it left briefly but came back. About the only other thing I can think of doing, besides elevating the chlorine back up for additional days, is to add poly.

The back of the bottle (60%) says 11 to 17 oz per 10k gallons. that would be about 28 oz to the whole quart full. But I was at another store today and saw that another brand of same stuff, same concentration, said 8 oz per 10k of pool? How much should I add?

Also, ch levels still elevated. Should I go ahead and add now, or wait for ch to come back to some level?

thanks