So introducing bicarbonate (CO2 dissolved in water at this pH mostly
takes the form of bicarbonic acid) into water will not increase
"carbonate hardness"? I'm not sure I understand.

Baking soda will increaase the KH. That's what I said. I was arguing with
someone who insisted you could increase your KH by injecting CO2 gas into the
water.


Leigh

http://www.fortunecity.com/lavender/halloween/881/