That's true, the pooping thing. In another conversation on here we discovered the long poop strings even have a funny name, we call them "plecorations" cos they will soon be adorning every plant in your tank if you don't vac every day!
Oh and forget the plants in the tank too....big plecs route them out and dig them up for no apparent reason. Sometimes my big two do it just wandering past them, but other times they go out of their way to dig them out. They are odd creatures. They seem to do it to amuse themselves.
Sailfins are way cool though, I have one (maybe 2, waiting for it to grow up a bit) and the big one floats upside down eating on the surface, he also stands upright on the end of his tail when he has managed to catch a tubifex cube, so he can eat it without losing it.