Tank looks nice! Did you use any hardener in the Rustoleum? I think it's about the same as the Alkyd enamel paint that Tractor Supply sells for tractors and implements. They sell a hardener you can add to it, and it supposedly makes it dry quicker and makes it retain the shine much longer.
I did add hardener. I thinned it progressively more each coat as well. I think the hardener I had was from Krylon. It was 96 today so I sprayed it in the morning and the sun just baked it all day.
