My co2

I have heard the baking soda is to help stabilize the pH (keep it up). Yeast will grow at different rates depending on things like temperature and pH. For use in the aquarium I would guess that the pH wouldn't get low enough in a CO2 reactor to kill yeast; starvation or alcohol levels would likely be the culprit.

One of the simplest ways to diffuse CO2 is to add an airstone. The airstone affectively increases the surface contact between CO2 and the water. Lots of small bubbles vs a few large ones. I hate to do it, but I would recommend you search the forums for some different methods of CO2 diffusion... Kind of defeats the purpose of a forum, I know...
 
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