"Ok, listen, as Rick said if t
"Ok, listen, as Rick said if the boat is used in fresh and trailered there is no need to bottom paint because the boat's not in the water long enough to accumulate growth. No barnacle problem either.
As MakoMark said, if a new boat is to be bottom painted it must first be dewaxed. That's because a wax is used as a parting agent so the hull will come out of the mold. You in NO WAY sand off the gelcoat. If you do that, first you be at it for a month ansd secondly you be exposing the substrate or laminate underneath wich is what the gelcoat is supposed to protect.Dewaxed & scuffed to give it some "tooth". Followed by a sandless primer coat not a barrier coat. A barrier coat is an epoxy or Vinylester coating that is applied to inhibit water absorption through older gelcoat or after blister repairs. It's time consuming and a bit expensive. Just about all newer boats don't need this as most of them use a vinylester layer behind the gelcoat in the first layup.
Now, if you've decided to go with an ablative paint such as Micron or Petits' Ultima, you first put on a coat of a contrasting color, over the primer, followed by two coats of the color of choice. Doesn't matter if it's lighter or darker. The reasoning is that when you start to see the contrast color you know it's time for a touch up or repaint. Most high quality ablatives are multi-seasonal and are of course meant to wear away with use. Most "hard" paints do not wear away and should be reapplied each season unless stated it will go more than one season.
There's also the waterbased paint such as Aqua-Gard but the procedures are pretty much the same.
Hope this helps some of you who were unsure."