OK Tom this is what i am alluding to. Are there natural waterways that have high KH values say 6 degrees and above , but the pH below 7.0 . I know this seems to be a contraindication but is
it possible? Whould such a body of water have a higher concentration of CO2?

Tom let's have a body of water. If i artificially load the water with carbonates/bicarbonates and then reduce the pH by adding an organic acid like acetic or citric acid, am i then stimulating an in vitro biogenic decalcification model that will lead to an intrinsic build up of CO2 albeit with high TDS??

LAKA