CH and pH


Well-known member
Jun 16, 2016
Peoria, AZ
Hi Folks,

I'm in Phoenix with tap water that is highly calcified. It seems not uncommon here to run CH levels well over 1000+ between water changes. I'm no stranger to this, but may be at my highest level yet which is 1700 CH. At this point (according to poolmath) I'm finding that at my current set-up (TA 70, Temp 90-95, Avg. pH 7.3-7.5, CYA 60) I would need to keep the pH around 7.0 to maintain a CSI index close to neutral unless I try to drive down TA into the 50s.

Question is is 1700 about the limit here to change the water, or can I run 7.0 safely with such high CH? Wouldn't it still corrode metals?