i own a paint store and i wil say use a low VOC paint and let it cure ( dry) for at least 4 days before putting it on the tank if the tank is stock. as paint drys it relases chmecials . it will take a week for paint to fully dry. the darker the color the more VOs are in it so just let it dry for a while and you should be ok also if it will be stained us a marine spar varnish as the clear coat as that is diseinged for high humidity areas and will hold up the best but apply the spar varnish in the garage as it has a nasty odor and lots of fumes let it dry 10 days before placing on the tank. if you want good light reflection you m=ay use an alumian paint but do not leave the full can in you car or sunlight as the heat can cause the WET paint to expand( blow the top of the can) and get paint every where use same precautions as with spar varnish