The one thing I don't get is how the TA/CYA is factored into the pool math CSI calculations and yet not produce the needed adjustment information when not in the proper range for chemical balance . The CSI does not suggest what you need to do to get CSI balanced at all as the pool math does in the other sections dealing with individual chemicals and maybe that's the aqueous heal that causes conflict in the application. Once you know the CSI is off and not balanced then you have to go plug in numbers into various areas that effect CSI till it gives you a good number result which is not very scientific or ideal. Making adjustments to fix the CSI may not correlate with the individual recommendations then. CSI calculations may take into consideration the carbonate vs cyanurate (non buffering) portion of TA (on high CYA concentrations only, since minimal levels would not have much impact) I don't know, along with CH, PH and CYA plus salt but leaves you hanging on where the issue lies to fix it.
I am finding I am holding my PH more steady at the higher TA of 100ppm (if we did adjust the TA factor based on excessive CYA of 80 x .33 just for sake of argument, it would mean TA is really at 74 ppm), then if you wanted your true TA buffering at 100ppm as inputed into the pool math calculator to get the CSI balanced it would need to be increased to 124ppm.
The point is if the CYA is within proper range, this whole thing is mute and the pool math seems to deal with this by recommending draining your pool water based solely on the CYA level alone as the solution. What I have determined because no other adjusts are indicated that's just how the pool math calculators deals with it (except for Taylors). I don't like things I can't see and that is a problem when it comes to this topic because the pool math CSI calculations are not visible and transparent but it generates results we need to deal with now and draining a pool is not an immediate option at the time. I may not be a water expert but I'm definitely not stupid. Thanks for all the input it has been very informative