The only thing I want to do is remove the corrosion on the piece and shine up the metal so it looks like it did when it was new. The epoxy coating I plan on doing is just a thin clear coat that will prevent contact of water and metal. I plan on keeping the original glass and plumbing in the tank. I just don't believe it is safe to have any copper containing metal in contact with water and aquatic life. If copper is used to kill parasites then all you need to do to kill anything else is just increase the concentration. If I clear coat the outside of the plumbing I see no harm to its originality. It must have been coated with something originally or it would have turned completely green. Although I'm starting to wonder if the plumbing may actually be bronze rather than copper. Either way it would have to have been sealed with something or be bronze or brass or both the intake and output pipes would be green. I can place vinyl hose inside the pipes which can't be seen and is removable. I'm thinking about trying to have the inside of the fountain arms plated with a non-reactive metal because the diameter is just too small for an internal hose. I am aware that vintage electrical component reproductions are available. You can see what I did with the lamp over my Jewel tank in one of my other posts. I plan on leaving the stand alone except for the top which is really corroded and the nickel accents. The entire stand is either brass or bronze so would probably look great if the paint were stripped off but then it wouldn't be original so I'm leaving it alone.
Better Living Through Chemistry