What's That Wavy Octocoral?

The Purple Frilly Gorgonian (Pseudoterogorgia elisabethi), is aptly, if unimaginatively named. it. The appearance, when the polyps are extended, is a feather-like plume which gives it a frilly look.  These polyps are one of two ways Gorgonians get energy.  Their polyps catch passing microalgae, zooalagae and detritus which are utilized as food for this Octocoral.  They also feed through a symbiotic relationship with zooxanthellae, which produce sugar excess to their own needs in the presence of sunlight, which is consumed by the gorgonian, making them effectively photosynthetic.  Purple Frillys are generally found in deeper waters (near 100 feet) which means they are somewhat more dependent on supplemental food than some species more commonly found in shallower water.

P. elisabethae has been studied for decades because it produces bioactive compounds called pseudopterosins, seco-pseudopterosins and elisabethadione. These compounds have been shown to have anti-inflammatory and selective analgesic properties. The Gorgonian uses these compounds for defense and perhaps reproduction. Pseudopterosins act as a deterrent for most microbes and predators, through there is one snail that feeds on sea plumes that doesn't seem to mind it. The Flamingo Tongue Snail is a common predator of all Caribbean Octocorals, though generally prefers some of the other gorgonian species.

Found throughout the tropical Caribbean and Atlantic Ocean, these gorgonians are typically discovered near coral reef overhangs and ledges for the rich source of flow-by food.  The average size of an adult Purple Frilly is anywhere from about 5 inches high to more than 20! Pseudopterogorgia elisabethae has distinct life stages, a larval stage that is motile (can move around), and as adults they are sessile (stuck in one place forever) and will asexually reproduce more Purple Frillys to form a colony, which by the nature of self reproduction, are all one sex. Sexual reproduction also occurs, where males release sperm into the water current where it is carried to females holding eggs in their branches. These eggs are fertilized, then develop into planula over 1-2 days which are released into the currents and set free! Spawning is not a mass event for this gorgonian, but rather a consistent effort.

For a long time, people shied away from keeping Gorgonians because they were perceived as difficult specimens to keep.  While I am not suggesting a brand-new aquarium hobbyist should put the gorgonian on his list to come home with day one, they are no more work than keeping stony corals or clams happy.  The primary keys to keeping gorgonians is to protect them, feed them and call them George (do not pet them).  First, they should be firmly attached to your rockwork, as gorgonians are susceptible to physical damage from falling. Second they should be fed, and we rely heavily on Nutramar's Live Microalgae product line here; there is no better nutrition for filter feeders available.  Third, it doesn't actually matter what you name them, but do give them tankmates that will not pester them; this means no fish that are known nippers like butterflies etc.  Lastly, pay attention to flow. Gorgonians love flow, but they love a turbulent and gentle flow.  No laminar (full blast from direct powerhead exposure) current.  Wavemakers are great for all octocorals, and on top of this, are amazing for the display of them as well.

There is no good reason why you intermediate level aquarists aren't keeping a Purple Frilly gorgonian. Like keeping any invertebrates, they have some demands, but none of them are onerous.  Make sure your aquarium is ticking all the boxes, stable temp around 78, pH between 8.1 and 8.4, specific gravity about 1.025.  More important than these exact numbers is the stability of them.  Don't skimp on water changes, feed your new frilly and watch as it flows in the current of your aquarium for years to come.