I've owned a new Catalina 310 for about a year. My wife and I went on an overnight and two unusual things happened. 1) we ran aground and Boat U.S. got us free by inducing significant heel by pulling on the spare halyard while I motored forward. 2) our first overnighter and, how shall I put this, the first time the head had been really used by a man (OK, I pooped!). Later, I tried to discharge using the macerator pump and when I flipped on the breaker, it made like a thump noise, but wouldn't run. The manual says that at excessive heel, the holding tank vent could get fluid in it, though when the heeling occured, the tank was practically empty. Anyone know if this sounds like a clogged vent hose or a clogged macerator (due to excessive poop)? If the vent, how best to clear it of fluid? If the macerator, what do I do? Would a pump-out help? Thanks!