"blank" wrote in message
...

"Iain Miller" wrote in message
...


Increasing the Kh will not increase your CO2 level....only adding CO2
does
that (!)
I have read that water with a high KH holds CO2 better than low KH, so
that's why I'm attempting this.

Increasing KH without altering CO2 will increase your Ph so I'm not
quite
sure how you managed to add Baking soda & not affect Ph....it doesn't
compute - suggest you test it again.

I've read that the pH will rise, but not necessarily in direct proportion.
My understanding (such as it is) was that I would be able to raise the KH
somewhat, without an immediate, correlative effect on pH. So I figured I
am
OK so far. But will check it again tomorrow.

SNIP ....

If kH is the only thing buffering a tank, adding baking soda will give you a
rise in pH, however lots of other chemicals in the mix can minimize the
affect of adding some chemical increase kH. Gravel really full of organic
material is one of them. I'm sure a chemist could suggest others. Seachem
sells an acid buffer that you use with an alkaline buffer to set a tanks pH.
It will suppress the response of adding baking soda.

Any chemists around?

Bob