>Early on in our fulltiming, some years ago, we were cautioned by some
>old-timers who were cleaning out a holding tank filled with dried waste,
>never to sit with our dump valves open, now we really understand why.
 

Good advice, for sure. FWIW, I leave my greywater valve open, so I can take
long showers and not drain the tank every couple of days. I've heard that
it's OK...is it?

Ned