Thanks but we boat when the weather is cool, work on the boat in the hot and humid. I put an A/C on the boat mostly for summer chores. With guidance from your book, I put all my fittings on top, so changing the vent hose is just removing an easily acessible hose clamp. We pump out on the way home from cruising, but with a taper on the pick-up tubes, we can't empty the tank completely even when we pump overboard.
We have LOTS of electricity on board, but I have other places to spend $317, so no aerator just yet.
Anyway, it's just a whiff when someone flushes. Makes me sure the vent is open, not plugged. No odor at all other times, not gonna give up cruising in the good weather just for an ocasional whiff.