Here is a new device that is coming onto the market that would be a lot easier to use. no pricing just yet.
https://www.atlas-scientific.com/pro...s/ezo-co2.html
However in a thread on R<2>R between RHF and a couple of Alkalinity tester people, they indicated that to have a hope of being able to accurately calculate Alkalinity based on PH and CO2, that you would need an accuracy of 2-3 ppm for the CO2 reading. Which none of the reasonable priced detectors seem to be able to do (including the one I just posted).
Dennis