I've had my Aerotank's for almost two weeks now, and I love them. I even ordered the bases for my protanks. Here's my problem, while recommending the Aerotank to a coworker, I let him borrow it to try it out. He closed the valve all the way (why would he do that?) and now it is jammed closed. I've tried soaking it in hot water, freezing it and everything short of putting in the vise and using pliers (don't want to ruin the finish or the knurled ring.) Any one else have this issue? Solutions?