kH and RO Relationship
I have a question regarding the Kh of RO water relationship.
I just recently bought an RO unit and I am trying to figure out my CO2 content. When you compare the PH of 7 and a kH of 0 on a CO2 Chart it should be 1.5, which is it, but this means it's very unstable right? If I want to add enough CO2 to get to my target range it would have to drop the PH all the way down to 6.3. I'm raising discus, but not Heckles so I want my ph at about 6.8. From what I understand ideal water has a Gh and kH between 3 and 6.
From what I can understand of this tangled web is that if I want a PH of 6.8 I need a kH of 4 which would give me a CO2 of 15ppm, but I would have to add NaCHO3. Is this the best way? Why is it that RO Right and other reconstructing agents only add Gh and don't rebuffed the water with kH.