I just noticed in this post that Steve (medvampire) found that his pool with CH 350 and TA 200 gets cloudy when the pH gets above 7.8 so that means roughly a saturation index (LSI or CSI) of around 0.7 - 0.75 (depending on temperature which I don't know). So my statement about a 1.0 saturation index was true for one person, but not for another.