Class A Diesel-Gray Tank

Mr.Mark wrote:
We leave the valves closed most of the time. If we run the washer and go out to lunch, etc., I'll open the gray tank as not to let it over fill. We have a 70 gallon grey tank so there is plenty of room.

But, I always plan on the gray tank being almost full when it's time to dump the black tank. It just makes for a better cleaning of the sewer hose after the black tank is emptied.

MM.

Open? Closed? As in many things with RV'ing - it depends! If your are staying somewhere for a few months, then leaving the Grey open for longer periods is probably not going to hurt you too much. Factor the scum/residue build up as others have pointed out. If you are a 'few days in a park' and then go kind of traveler, then we following Mark's way is a good way to go.

After fighting to clear out a pyramid when we bought our first new used Bounder in 2006, I very carefully administer the tanks!

We try to get at least 1/2 tank of Black before draining, running dumping water in as needed to get it to that level.

For us, typically:

Grey we keep closed until needing to dump, and when we are close to leaving, we work it to time it to be 3/4 full before the final dump and go...

Except when Boondocking, we try to not travel with tanks too full. If we know we've an easy route, and short distance to our next stop - we will sometimes travel with a 1/4 tank or under Black.

Yep, it depends!

Best to all, and what a great invention the tank flushers were!!!
Smitty