So, the bathtub drain finally clogged. I ran a heavy-duty snake down the drain and only got about 12" before it wouldn't go anywhere. I took the pipe apart below the tub, and the pipe was completely clogged with a dark red, hard sludge. It was so hard that I had to actually chip away at it with a screwdriver to clear the pipe out. It had no odor. It had been there a loooong time. But it stopped before it got to where the sink drain joined the line, so it was very specific as to where it was in the line.
What could it be?
Additionally, I couldn't get ALL traces of it out (though the pipe itself is pretty much clear). Anything I can do to get rid of it, other than just running purely hot water down the drain for 15 minutes?
I thought maybe it was something the kids put down there like clay, Play-Dough, or even poop, but it had been there for a long time given how hard it was--longer than we had been living there.
I tried Googling but didn't find anything.