I've read here several times that you can keep your pH a little higher if your CYA level is high (mine is 150); but is there a chart somewhere that I could use to determine what my pH should be? I'm thinking a new column added to the best guess CYA chart for pH? My pH is 7.9 now - do I need to lower it with a CYA of 150?

Here are the other numbers:

16,400 gallon vinyl liner
TC 9.2
FC 7.4
Alkalinity - I have a TA of 197 and an adjusted alkalinity of 152. This is an Alex test report, and it's assuming that I'm going to add 3 pounds of pH decreaser.

I've been partially draining and refilling to reduce my CYA. It's gone from 330 to 150, but today my total hardness is 239. Should I try to lower that? I've read that draining and refilling is the way to do that, but apparently it's not working in my case because the hardness has increased since I've been doing that. I'm just not sure if it's high enough to worry about.