Each gorgonian polyp has eight tentacles which catch plankton and particulate matter that is consumed. This process, called filter feeding, is facilitated when the "fan" is oriented across the prevailing current to maximise water flow to the gorgonian and hence food supply.
Some gorgonians contain algae, or zooxanthellae. This symbiotic relationship assists in giving the gorgonian nutrition via photosynthesis. Gorgonians possessing zooxanthellae are usually characterized by brownish polyps.
Gorgonians are found primarily in shallow waters, though some have been found at depths of several thousand feet.[3][6] The size, shape, and appearance of gorgonians can be correlated with their location. The more fan-shaped and flexible gorgonians tend to populate shallower areas with strong currents, while the taller, thinner, and stiffer gorgonians can be found in deeper, calmer waters.[3]
Other fauna, such as hydrozoa, bryozoa, and brittle stars, are known to dwell within the branches of gorgonian colonies.[10] The pygmy seahorse not only makes certain species of gorgonians its home, but closely resembles its host and is thus well camouflaged.[11] Two species of pygmy seahorse, Hippocampus bargibanti and Hippocampus denise, are obligate residents on gorgonians. H. bargibanti is limited to two species in a single genus.
Gorgonians produce unusual organic compounds in their tissues, particularly diterpenes, and some of these are important candidates for new drugs.[12] These compounds may be part of the chemical defenses produced by gorgonians to render their tissue distasteful to potential predators.[13] Despite these chemical defenses, the tissues of gorgonians are prey for flamingo tongue snails of the genus Cyphoma, the fireworm Hermodice sp., and their polyps are food for butterflyfishes [14]