morris

From what i understand about kh & ph is that it goes hand in hand:
if you raise kh, ph will raise to and visa versa

then how is it possible that some people say there kh is say 1 deg, and ph say 7.2 and other's kh is say 4 deg, and ph say 6.8

Isn't it suppose to be the same all over the world, cause if you've got a higher ph, you'll oatomatically have a higher kh, same goes for lower values?

where i live in South Africa, our values are ph-7, kh-2
After adding co2 the ph goes down to +-6, and kh to 0.5

Now some people recomend to raise the kh, add baking soda, wich again raise the ph, but then they also add to raise kh, add baking soda, and add more co2 not to raise the ph, but by adding more co2, won't that again lower the kh?

I'm seriously confused, or am i just missing something?