Soft coral

Soft corals are any of the species of corals belonging to the taxonomic order Alcyonacea.

Anatomy
The regular octocoral polyp has a cylindrical columnar body ending in a mouth and is surrounded by eight pinnate tentacles. The inner anatomy is very ancient with a large stomach and only one opening which is the mouth. Through a nervous network is how the colonies of polyps communicate while exchanging food and information. Gorgonin is the protein that the horny axis is mainly composed. Coenenchyme is the colonial tissue in which the skeleton is covered by. These are the make-ups of the sea fan that is another type of soft coral.

Reproduction
Alcyonacea reproduce asexually by budding and fragmentation and sexually via egg and sperm production. If you are looking and cutting and grafting you could think of them to be artificially propagated. It could still re-grow and live its own life if you broke off a piece and glued it to a hard substance.

Ecology
The soft corals are passive filter feeders that are dominating and prefer the shaded habitat. The corals polyp tentacles make it possible for it to collect particles from the water that is just floating about. One of the defense mechanisms that it has is its nematocysts, which are the stinging cells that paralyze its motile prey. Soft corals have few enemies. Fish, such as the butterflyfish, and mollusks will tend to chew on them, but do not have a massively damaging effect on the corals. The main reason you see nothing usually growing on corals is that they are toxic to some species. The chemical effects that they can have on other life forms are call terpenoids and that is basically a poison to harm others. 

Related References

 * Alcyonacea Wikispecies
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