[JABURKHOLDER]

This discussion just made me think about my regiment. I normally keep both grey water tank valves open until two days before I break camp. I then close them and let them fill because I use that water to flush the pipes and sewer hose. I believe they were open during my black tank flush. I'll close those valves before my next flush. If that was the problem, then I'll look at the galley and bathroom traps. If that wasn't the problem I'll try shutting off the front ac before flushing.

I don't get the smell in the basement but the basement is cool from the ac. Need to look into blocking all those vents mentioned. AC works great but blocking those vents can make it better.

Thanks for the ideas. I was stymied.