^ Gross? Noooo, heck I told the family halfway through a meatloaf dinner!
No, PO was just a negligent slob. I believe his stated use, which was 1 camping trip back in, idk, 2017 or 2018, and a few weeks of nightly use as a spare bedroom only.
This camper was/is basically brand new and 4 years old, but the PO's knowledge and life of "give a rip" about it was very low.
Consider, once I put enough gas in the gas tank to get the fuel station to work, what first came out of the tank also looked like it should have come out of the black tank!! PO never put ANY gas in it. In fact he swore it was a LP fired generator.
He just didn't dump the black tank, pretty sure of it and my adding water and messing with the systems stirred up some old crud!