China's magically synchronized fish: A case of animal cruelty?

The video: During last week's Lunar New Year festival, Chinese state television aired a widely watched controversial segment in which magician Yu Fandong showed off six goldfish swimming perfectly in sync with each other. (View clip below.) But how did this trick work? Some say that Fandong must have cruelly manipulated the fish to swim in formation, either by implanting magnets in their stomachs or controlling them via an electric current. The magician insists that the goldfish are "living happily." Still, Chinese television canceled a scheduled encore performance.
The reaction: We shouldn't exploit these animals for entertainment, says Qing Shaona, director of the Capital Animal Welfare Association, as quoted by NPR. "I think this is just wrong." Others are more awed than outraged. "I've been buying and selling magic since 1948," says British magic-shop proprietor Betty Davenport, as quoted in The Guardian, and "no magic that I know of" could produce that effect. See the puzzling, synchronized goldfish for yourself: