question about co2 and ph

[m-man]

i was curious if your ph is 6.5 and you have 2kh, thats 19ppm co2, now if you were to add baking soda to raise the ph, would that knock out some co2 as the ph goes up, or does it just raise ph leaving the co2 the same,
and if it does would that make calculating co2 from then on innacurate.

 

[rkilling1]

adding baking soda increases both the Ph and KH. it will not change the CO2 or how it is calculated.

 

[malkore]

adding baking soda increases both the Ph and KH. it will not change the CO2 or how it is calculated.

bingo. increasing Kh with baking soda will proportionally raise pH, so afterwards you'll still have the same CO2 level...possibly less actually, since a higher Kh indicates more 'resistence' to pH changes.
But it'd probably only be a couple ppm less, and it really depends if you just bumped Kh to like, 4dKh, or way up to 8dKh.