Alright all,
latest results, I think I made an initial mistake on CH levels, lighting wasn't great, so did outside in natural light. The color change very gradual. I will most likely get a drain and replace in off season going so I can also clean the scale ring around the tile and start with fresh fill water.
FC 4.5
PH 7.4
TA 70
CH 900 So the water starts turning purple at 700, getting more blue at 800, and a definite blue at 900. So I assume it is actually 900?
CYA 60
salt 3800
CSI .02
It's just about there, but again, given the hard water, solids floating in pool, and scale ring, I think I will do a drain, clean and refill when it gets cooler.
Thanks!