Originally Posted by rattleNsmoke
Wow, what a tangle of spaghetti.
I went with three separate quick disconnects and "keyed" in such a way (male/female fittings AND two different brands of quick connects) that it's impossible to hook the black tank flush hose to either of the fresh water fittings and vice/versa. Even with a back flush preventer, I don't want to chance getting sewage bacteria in my fresh water supply.
I may add a splitter on the fresh so I can feed either line from one hose, but BW flush will always be a separate hose/fitting at my house.