I Guess I’m being a little bit of a perfectionist and guilty of number chasing. The simple pH>7.2; TA&CH>100 are a great benchmark to know. Thanks for all of your help.

I believe I have discovered that the stains on the pool are organic. It appears to be very dead algae. It is stuck on all of the fiberglass walls and some spots on the plaster. I brushed the walls twice and could still make a line on it with just my finger. Any recommendations for a good scrubbing tool? My plan is to get in the pool with a box magic erasers and go to town. I’m not afraid of a little (or a lot!) of sweat equity.
I imagine once the sides are physically clean the water will be perfectly blue/clear.

And Poolmom - yes it was a typo (250).

-Cheers!