After a recent drain/refill, I've been concerned about my CH @ 140ppm (now lower, 120, I'm assuming due to rain - ~2" - as I've had no top offs since that reduction). However, after much reading here today, I've been educated on CSI (I previously ignored that section in the calc) and the fact that my CH will rise as I top off due to evaporation (this I also learned from reading here today: CH does not evaporate and the resulting top-off adds whatever CH is in the tap). Thank you TFP experts!
Sooooo, Since my CSI is -.35 and other #'s are looking good, I'm thinking (here I go thinking again - PLEASE correct me if I'm off) I shouldn't worry about the 120ppm CH. We usually have high evaporation and my fill (from outside tap - city water) is 50ppm CH (I was quite surprised at this as I'm in Austin - limestone - and we're known for very hard water) so it should rise over the summer. Again, if I'm understanding correctly, since my CSI is in the safe range I shouldn't have to worry about my pool water pulling calcium from any other source.
CYA 30 (I should note that I currently have several 3" pucks in the in-line chlorinator just to raise CYA. I will remove once it comes up a little - I normally use only bleach to chlorinate)
p.s. my next inquiry will be to the city to see if maybe they're now using reverse osmosis or some such to treat the water as I was amazed at the 50ppm CH reading from tap - we don't have a water softener (besides, the outside taps' source should be from the water that has not yet entered the softener - from the line between the city tap and the softener)