Thanks for the responses, fellas---I was wondering if attacking the source with bleach was a remedy---I know that there's a big difference in dousing your bathroom at home with Clorox to remove mildew, as it works immediately, but using it on a boat and breathing bleach fumes while trying to sleep aboard is no one's idea of fun. Also, I'm guessing some parts of the structure would be eventually damaged by recurrent bleach use, whereas a dehumidifier is portable and controllable....moisture and temperature combined appear to be the culprits, hmmm??