Originally Posted by smata67
Close the valve and just leave it connected to the tank?
Or you could spring for one of these.
That's a regulator/flow meter on a 20 cubic foot tank (nearly identical size to a 5 pound CO2 tank). Got it all an a local Airgas outlet. I last had it filled nearly two years ago and have brewed nearly 400 gallons of beer with it since. That would be a lot of little red O2 bottles. The needle is well down in the "refill" zone now but it still has a few more batches left in it...