This is crazy! These Goldfish are actually living in a working Deep Fryer! Fish live in the water below the heated oil that sits on top of the water. Any crumbs fall down through to the water, where the goldfish can safely eat them. Amazing!
From: http://www.youtube.com/watch?v=ZH96MhITOlk
there is a cooling system between the water and the oil. It took them ten years to develop it. So the bits of tempura batter fall down and stick together, which keeps the oil clean (the bits don't float around and burn). Also, if you throw frozen pieces of food into a fryer, usually the oil will react violently, but now the waters sinks and cools instead of becoming vapor.