Dennis - it was that very fish tank adapter (I also have one) that made me think of what Orv discussed
. I suppose the principle is the same. It's truly not a leak, or I would see something on the ground when parked, and it was bone dry the whole trip.
Quite a strange concept, but if it means I need to check the tank fill every once in a while at the compground, so be it. It may not be worth too much investigation. The trip was otherwise flawless in the new Monty - again. The wife looked at me when we pulled up to the house and said - WOW-nothing broke!