condemned tank

[scubadog76]

A few things...
First, bummer about the tank It's good that your dealing with them at a store level first before MNSCUBA level. Hell hath no fiery like a diver scorn!! You'll get farther keeping it civilized like your doing.
Next, when I was filling my tanks today, I asked a reliable source about what kind of regulation there is on a "passable" tank. The stickers he said, come from a printer, no state agency or anything like that. There is nothing like the Weights and measures group for gasoline. It's an industry standard not a national code to VIP tanks. I would truly hope that no shops in town would push a tank through to keep from losing a buck. I have a steel dive knife that was left in a damp tub by accident for about 3 months. It did rust but nothing that steel wool couldn't take care of.
Also, how does moisture get in a tank. Empty a tank with the valve all the way open, take the valve off in a damp area, compressors with bad filters are all that come to mind. The fair resolution I feel would be both sides chipping in a little. Buyer-be-ware comes to mind as mentioned by others but it is also life support equipt. that should be in tip top shape or retired.