Clownfish have a symbiotic relationship with anemones. Alot of anemones eat fish or are poisonous and fish stay away from them. The Percula clownfish is the exception to the rule. They will choose an anemone as a home and usually not stray to far from it. If they get threatened by a larger fish, they can hide in the anemone, or alot of the time you will see one "wallowing" around in one. For some photos look here
http://www.exotictropicals.com/encyc...ruepercula.htm