Most of the many kinds of anemones living on coral reefs stay hidden in crevices or under rocks. But large Heteractis anemones are prominent and visible residents on Indo-Pacific reefs. With their bases anchored to rocks or rubble, these anemones spread their crowns of stinging tentacles wide, up to three feet (1 m) across. Like their cousins the reef-building corals, these anemones have algae living inside their tissues. The algae produce sugars and proteins that help nourish the anemones.
The large anemones often host communities of other animals as well. Certain shrimp and crabs live on anemones, and a single anemone may be home to several kinds of anemonefishes.
Many of these anemones are collected each year for the pet trade. Since they live for a long time and reproduce slowly, overcollection threatens their survival in the wild.
These anemones may live 100 years or more.
A single large anemone may host several kinds of anemonefishes.