prerequisite to co2?

[7Enigma]

I'm going to go out on a limb and guess that the baking powder might be in there to do one or a combination of 3 things:

1. slightly buffer against pH changes

2. supply some limiting nutrient that the yeast depletes

3. supply CO2 during the lagtime before the yeast ramps up CO2 production

No idea if any or all of these play a role, and I can't remember if the recipe I read ever said why they used it, but it worked great and I'm going to continue using it.

As for the amount of yeast to add, my recipe just said to add 1 package of the dry yeast. Mine came in a 3-pack for $1.49 or something, no idea how much yeast was in each one. In my last batch on top of screwing up and adding baking soda which slowed the reaction down, I also only added 2/3 or so of the package. The combination of the baking soda and the slightly less yeast along with my cold house temp (50-65F) is the perfect recipe for my tank..

Turns out it was #1:

One way that has been proposed is to add baking powder as a buffer to the mixture to regulate the acids

also turns out it might be a bad idea:

Conversely, sodium ions are also toxic to yeast, so once the sodium biphosphate has been broken down by the acids, the free sodium ions tend to kill off more yeast cells. So this method is only a transparent fix to the yeast kill-off.