Ok here's how the story goes.
This happened when I was in grade school.
My grandmother had come to visit, and she wanted to do something nice for us, by cleaning the house.
We had an aquarium with fish, and a salamander. On the aquarium we had one of those aquarium heaters, so the fish would not freeze to death in winter.
My grandmother did not know that we only plugged the heater in at night and set the knob on low.
She plugged in the heater, turned the knob all the way up, and went about her business.
In summary, my mother came home to a clean house and a tank with a floating, bloated salamander.
There's another story involving hamsters and cannibalism in my house, but that's another story.