Conrad & Tricia Holsomback wrote:

> 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.

Not so bad to leave the gray water valve open, as long as you let the tank fill
up and flush it out once in a while. Leaving the black water valve open is, as
you say, a recipe for disaster. Before dumping the black water, let the gray
water tank fill up, then you can use it to flush the hose after dumping the
black water.

Just driving down the road, with the black water tank half full or so, and some
waste digester in there, should loosen the deposits in time. But it will be a
slow process unless you go in there with a water wand and blast the worst of it
loose -- after it has been well softened by exposure to the appropriate
holding-tank additives.

John

Susi and John Burchard
Tepe Gawra Salukis
saluqi@ix.netcom.com