I used a lot of water yesterday while making dinner and cleaning up.
This morning my shower was full of brown water.
I thought the worst of course, afraid it was not gray water that was floating my shower rug but looking closely and sniffing, I realized it was wash up dishes water and ran out to empty both tanks.
With a sign of relief, I see the water draining and the ring of oil from my pasta sauce and soap suds clarified it was from the gray water tank.
I didn’t know that would happen, did you? But of course it’s obvious to one who thinks, where else could it go? I don’t remember to empty my tanks daily, now I will, glad it wasn’t the black water tank.
I guess the same could happen, but up the toilet.