Wondering if anyone knows of a sealant that can be used on vinyl to stop mildew? My father owns a 2008 Suntracker pontoon boat, and every time we want to take it out, we have to deal with mildew all over the vinyl. The boat is always covered up, so its either you get mildew with the cover on, or you risk fading with the cover off. The only sure way we've discovered to removing the mildew effectively is by using bleach, which is a pain to do every time we take the boat out. Anyone know of a product that prevents this? Thanks.

Try Armorall or similar product.

You need to provide ventilation to stop the mildew.  Providing gaps for air to enter and escape might help, but it will also provide mice and other critters an easier access to a nice home for the off season.

One other thing you can do.  On a nice, dry sunny, breezy day, park the boat in the sunlight with all the compartments wide open and let it dry thoroughly.  Make sure there is no water in the hull.  Raise the bow of the boat and pull the plug.

Chances are the moisture on which the mildew thrived was in the boat, and the cover kept it there.

I keep mine in a garage and was told by the dealer to keep all the hatches open.  Even stored indoors if the compartments are the least bit damp, they will mildew.

Try Armorall or similar product.

You need to provide ventilation to stop the mildew. Providing gaps for air to enter and escape might help, but it will also provide mice and other critters an easier access to a nice home for the off season.

One other thing you can do. On a nice, dry sunny, breezy day, park the boat in the sunlight with all the compartments wide open and let it dry thoroughly. Make sure there is no water in the hull. Raise the bow of the boat and pull the plug.

Chances are the moisture on which the mildew thrived was in the boat, and the cover kept it there.

I keep mine in a garage and was told by the dealer to keep all the hatches open. Even stored indoors if the compartments are the least bit damp, they will mildew.

Thanks for the fast reply.  I was reading a little bit more about others having this same problem.  The consensus seems to be like you said, add vents.  Some people say they even put a small fan under the cover to circulate air better.  I was also reading about a product called RAMMO, which is supposedly supposed to prevent mold and mildew for 6 months after application.  It looks pretty interesting, heres the site: http://rammo.us/store/