You should have an outlet on the side of your hull where the sink and your ice chest can drain out. The sink and ice chest should probably have a "T" fitting where they can exit together through a single hull fitting. Just follow the hose from the bottom of the sink and the ice chest, and make a note of where the outlet is on your hull, and provide a hook up between those two hoses, to that outlet. If you can't tell which is which on the other side of a bulkhead, have someone pull on the hose so that you can identifiy it. Then you could mark that hose. One of those hoses feeds the sink from your water tank. Once you start poking around down in there, you'll find out where they all go. Good luck!Joe