Paul Higashikawa

O.K., guys, I figure since I often site this wonderful method as the top choice for DIY CO2 injection, I should therefore write an in-depth article on it so everyone can refer to it for future reference. This method, of course, is realized by Tarah Nyberg, whose article on this procedure can be found in TAG V17#2 Apr-Jun 2004 as well as an on-line PowerPoint file. I am merely summarizing what she has talked about. Anyone who is really interested in more detail should take a look at either of those two sources. Enough yapping; let's get right to it:

1. 1 cup of sugar per 2L of water. Water should be at room temperature; too high or too cold will inhibit the culture growth. Also, it is good to use tank water or dechlorinated water as chlorine is harmful to yeast.

2. Add 1~2tsp of protein drink mix. The author suggested using soy powder as a cheaper alternative, which is what I do, and it works great.

3. *Optional*Add 1T molasses or 1tsp ammonium sulfate(yeast growth benefits from ammonia, hence the use of tank water).

4. 1tsp baking soda to maintain pH stability.

5. One can opt to leave yeast from the previous mixture on the bottom of the container or use new batch. It is faster if the previous batch is saved and used.

There ya have it. I only listed the proper steps. As to the how and why each step is being done, you should refer to the original source as I've already mentioned. Everything listed here has a reason and wasn't conjured up out of the author's own imagination. She is an avid scientist who conducts experiments related to yeast cultures. All the credit goes to Professor Nyberg. Thank you all, and have a happy DIY CO2 adventure!!!


Paul