Originally Posted by Fingers
The gauge isn't an indicator of the amount of gas remaining. The liquid gas will vaporize to maintain head pressure until all the liquid is gone and then the pressure drops rapidly. What happened to you is normal.
unless he actually has a leak, which is possible. It's very hard to tell sometimes...whether it's a leak or whether you just ran out of gas because you dumped a bunch of CO2 into a new keg.
I second the starsan/soapy water test. Personally, I just emptied a half full co2 tank last night because I had my sparkling water turned up to 50psi...which, apparently, is the threshold for my regulator check valve
FOund out where the gas was coming out by spraying soapy water. So, to the OP: IIWY, when you get your tank refilled and hook it back up, I'd definitely spray starsan around all your connections, on the regulator, on the hoses, disconnects, keg O-rings, release valves, etc., just to be absolutely sure. There's a good chance that fingers is right, but just to be on the safe side, I'd test it.