I got a good one. We have 5 tanks, and sometimes you forget WHY you put certain things in certain tanks, etc.
So...we have this beautiful raccoon butterfly that recently developed a sudden liking for the sides of our zebra flounder. No good...since the flounder gets very upset when this pretty little fish tries to eat it's fringes.
So...while I'm deciding what to do with the butterfly, I put him in my invert/quarantine/holding/extra stuff tank thats underneath the main tank.
Cool, except, I have a beautiful hammer coral in there that is waiting for a home in the reef tank.
Guess what? Raccoon butterflies LOVE hammer coral. Mmmmmm.