Great idea Bobbo! I have the clear 90s on both of my tank outlets and have another for the exit end of my hose. I would like to find a clear Y but the opaque I have is sufficient.
I use the built in BWT flush nearly every time I dump my BWT. As Bobbo described, I open a dedicated hose to the flush after dumping had become a small trickle. My difference is that I'll close off the BWT valve and let the flush run for 3 minutes, then open. I'll do that for an many cycles as it takes to get a clear, "chunk-free" stream.
I am looking to put more clear pieces into my system. Anything that gives me a better indication of having properly cleaned my tanks, to me, is worth the time, effort and expense.
That said, anyone know if a good resource for RV plumbing supplies?