2part without affecting pH

[user48953]

I remember reading (a few months ago) about mixing baking soda with washing soda (baked baking soda) together.. the resulting solution would not affect the pH to either raise or drop; similar to the commercial buffers.. did i remember this correctly and does anyone know the formula?

thanks

[Randy Holmes-Farley]

It depends on the pH that you want to stabilize at, but it is mostly bakng soda and a small amount of washing soda (or baked baking soda). Something like 5-20% baked baking soda. More baked baking soda stabilizes a higher pH. The exact amount is not very important. If it seems to raise the pH too much, add less of the baked stuff.

[user48953]

Thanks for the quick response!

What would the ratio be if the target pH is 8.3? and would i just measure the pH of the solution after mixing it with RO?

[Randy Holmes-Farley]

No, the pH before adding it is not the issue. It is the pH after adding it that matters. For example, baking soda alone will have a pH above 8.2, but it will lower the pH of 8.2 seawater when added to it.

10% by weight baked baking soda (washing soda) would be a fine place to aim for pH 8.3.

[user48953]

ahh.. now it's starting to click together.

thanks for all your help :)

[Randy Holmes-Farley]

You're welcome.

Good luck. :)