Sea anemones are a really common offering in the marine aquarium trade. All types of species are brought in from carpet anemones, filter feeding tube anemones to increased bulb tip anemones.
While most individuals believe that they are corals, sea anemones are in fact under the phylum cnidaria, which strangely enough, includes the jellyfish. In their own bodies are comprised symbiotic algae called zooxanthellae which extract energy from light and feeds the sea anemone with their by-products.
Where they differ from corals are their ability to move from location to location. This behavior is commonly seen in captivity where the sea anemone will proceed around the aquarium until it’s found an appropriate spot.
Unfortunately this behavior is undesirable mainly because their tentacles contain stinging cells used to capture prey and as a defense mechanism. As they go around the aquarium, they may come into contact with and sting any corals that exist.
The sea anemone shares a symbiotic relationship with a number of creatures in the wild. The most famous of their hosts are the clown fish family. They also play host to damselfish, certain crabs and a variety of anemone shrimp which rely on it for protection against predators.
They are a tricky species to look after in a marine aquarium since they require strong water flow and very powerful lighting to succeed in the long run. If they die, they literally start to melt.
Unfortunately, the wonderful number of these creatures wind up dying in captivity because of improper conditions. This is a shame because in the wild they are known to reach a lifespan of a hundred years or longer. Some experts have pointed out they might not even die if conditions remain good.