I just received a 220 gal tank and the guy had painted the backside glass black on the outside. Not sure of what type of paint was used but is was sprayed on. Any ideals on the best way to remove it.
If its a glass tank just use a razor blade. If there's no fish in it the goof off or other paint remover would work well, just make sure if you get any inside the tank you clean it out real well. A razor blade has always worked well enough for me that I didn't need anything else