I used oil based house paint and matched it a shade under my exterior color. Heres before.
[img]http://www.***boat.com/image_center/data/500/57bilge_clean_up0005-med.jpg[/img]
Heres after, I used a primer sealer(Kilz) then laid the paint on with a couple of thick coats, takes awhile to dry, but its easy to touch up and easy to clean. You can splatter it with the accent of your choice.
[img]http://www.***boat.com/image_center/data/500/57blue_bilge0002-med.jpg[/img]
Good Luck
KC