Originally Posted by sailingdog
Mold can be fixed by using bleach...but bleach is very corrosive and will need to be rinsed out very thoroughly... it also attacks a lot of different materials, so should be used as little as possible. However, if you don't stop whatever is causing your bilge to fill with water....the mold will generally just come back. Any place that is not well-ventilated and damp is a prime growing medium for mold.
As for the forehatch, it may make more sense to replace the gasket/seal completely. Are you sure it is the gasket that is leaking??
The forehatch is leaking at the contact point where upper lid and lower lid meet. The gasket is good, when I sluice the decks there are no leaks. BUT when it rains for 5 days straight will cause a capillary action and there'd be about 1 drip / 10 mins. Not enough to replace the entire gasket, but just enough to drive me crazy.
The bilge is very dry during summer. However, in winter when there would be some moisture collecting on the walls, eventually some of that does make its way to the bilge -- hence the mold. If left for 5 months in winter, while still in the water the boat would have half-a-centimetre of water in the bilge. Hence my mold problem.
I've tossed in the bleach as you recommended. Sure enough, it made the mold white. It doesn't smell anymore after the bleach. The methyl hydrate, although it dried out the bilge, spread the smell all over the boat more.