I've had this spa a little over 2 years. My TA runs around 35 to maintain a good PH around 7.6. Of course on poolcalc my CSI is kinda far into the negative - around -4.
The water starts with a CH of around 80 and I've always just bumped it to 150 and left it there, but now I'm wondering if I shouldn't raise the CH to around 300 - which should give me a CSI of near 0.
So I'm just looking for a sanity check - does this plan make since?