I have a question about bottle size...from what I've read using a 2L bottle vs. a nutrafin canister will last longer due to the decreased alcohol concentration levels. My question is about the peformance of the 2L vs. the Nutrafin canister. Basically, which will produce the greatest amout of CO2 a day? My current mix in the Nutrafin canister is lasting right at two weeks, so if the 2L will produce CO2 at the same rate, and last longer, I'd like to switch. However, since I'm running the system on a 29G I want to have the highest possible rate of CO2 production, even if that means starting a new batch every two weeks vs. every 3 or 4. Thanks for the advice!