As of 12/1/14 we no longer fill CO2 tanks. The costs associated with doing so have slowly risen over the past few years and have reached a point where CO2 is no longer a feasible option for paintball. If you still use CO2 to power your paintball gun, it is time to make the switch to using Compressed Air. We do offer 5lb CO2 tank exchanges for beer kegerators.
More info here.