My neighbor keeps a spry 25-year-old, which used to bite my knuckles when I cleaned out his reef tank years ago as a kid. Clownfish may or may not become sexually mature adults. A strict hierarchy ...

Anemonefish, sometimes called clownfish, have been popular attractions in aquariums ever since Disney's animated film "Finding Nemo" arrived in cinemas in 2003. Living symbiotically with sea ...