I've got three aquariums. I think I forgot about them for a long time, and now the water is getting low, and there's a ring on them like a bathtub. The fish seem to have evolved, becoming strange combinations of the fish I used to have. One is like a combination of a pleco and a catfish.

Another catfish-related one has grown so large that he fills up nearly his entire tank, spilling out most of the water. He's bumping around so hard that he's moved his tank on its table, and now it's all askew.