[FastDave]

I've painted several ladder racks that I built in my shop with a very small air compressor and achieved excellent results even with the small pump and small tank. You just gotta take your time. Since you're only painting a tank I don't think you should have to worry so much about your air compressor specs.... unless you're a real "tech head" and then you'll want to go buy a newer, larger air compressor since this one job really does justify the expense! lol