What is a "tuxing" tank and/or "tuxing" valve? Whatever it is, if you're unsure about it's construction, safety, etc. then definitely get it tested. You can't afford to be less than 100% confident when it comes to high pressure air! That being said, your local scuba shop should be able to help with that.
~Mondo
PS
If you bought from Joe Brancato you wouldn't have to worry about anything!
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