CO2 from KH and pH

I worked it out by formula so it is much easier to

for KH=1, CO2(ppm)=3*10**(7-pH)

for other KH values, just multiply by KH, so
which looks remarkably like the equilibrium
equation for:

     H2O + CO2 = 2H+ + CO3--

Didn't I see this before in freshman chem about 30
years ago?
Dave Gomberg, Experimenta      San Francisco CA      gomberg at wcf_com