Im in the process of building a DIY Co2 maker using a 2 liter soda bottle. My question is this: From searching through many of the threads on this forum, I've seen a couple of mentions of a tank of water to put the soda bottle in. Is there a temperature the bottle should stay at to keep the yeast alive and producing CO2 or would it be alright to just keep the soda bottle around room temp (74*F on average). Thanks guys!