You installed that? Is it true you can't run the fan when you flush because the smell will come back up into the trailer?

Some people say a fan can pull odor into the trailer from the toilet but I haven't had that experience yet. I would think closing, then flushing would eliminate the problem, especially if it's a properly vented and treated black tank. I use this stuff to treat it and it is AMAZING at eliminating odor and breaking down waste. https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1