I would be worried about fouling the regulator by using the co2 in soda bottles.imatrout said:I'm interested too! However, for a nano tank, I think if somebody came up with a $10 device that could simultaneously puncture and seal plastice soda bottle cap, they would have a winner.
For 50 cents I can buy a 2 liter bottle of soda water. If I could get the CO2 out in BPM's, I think it could last a week or more supplying a 1-3 gallon tank. Maybe longer! You need a device that has a needle valve built in and a hose attachment, but on the other end, clamps to the bottle top, punctures it and forms a seal.
I will fill everyone in on the price when I recieve my quote from Leland, they sell directly to consumers.