Actually tanks can be refinished. There are Hydro companies that will "strip" clean and repaint tanks steel or Alm. Yes they must get a new hydro and inspection but we have sent out quite a few with excellent results. For steel it’s real clean to have them "Metalized" they come out looking new out of the box. Too bad none of these last any longer than the original. NO tank should be heated or have a grinder/sander or the like taken to the surface. All DOT markings must remain intact so they can be read as well as Tank ser #’s, fill limit.
Normal cost is about $85.00 but includes Hydro and cleaning. If your Dive shop doesn’t offer this service try New England Divers in Long Beach