Saltwater Aquarium Blog

Soft Corals

Soft Corals

The categorization, ‘soft coral’ represents a mind-bogglingly diverse group of species.  These coral species are classified together based on their lack of an external bony skeleton, like the stony corals.  While they do possess some elements of a calcified skeleton, this often exists as seemingly tiny slivers of the skeleton embedded in the soft flesh.   The majority of soft coral species available in the aquarium hobby belong to the order Alcyonacea—which includes star polyps, xenia, tree coral (Kenya tree, colt), leather coral and sinularia. Many of the soft coral species are reasonably easy to care for in the saltwater aquarium and have representative specimens that are well suited for aquarists of all skill levels.

Because the designation ‘soft coral’ can refer to any number of species, a generalization about husbandry and captive care is difficult.  However, many of the available species are hardy in nature and have photosynthetic symbiotic zooxanthellae. Several species are also thought to absorb nutrients from the water column as well. 

Pachyclavularia (green star polyps), Xenia and  Capnella (Kenya tree) species are ideally suited for beginners.  In fact, if you are not careful, some of these species may over-run your tank. So keep them away from areas you may want to grow more expensive species later and get ready to frag!

Saltwater Aquarium Blog Tip: The easiest way to frag some of the hardier, encrusting species of soft coral, is to place some live rock rubble (the small pieces of rock that break off and are at the bottom of your tank) and place them right next to the coral—touching lightly if possible.  Over time the coral will grow out and cover the rubble—you can then cut or tear it away and poof, you have a frag you can trade a friend or give to a newbie.

Advanced Aquarist Note: Some of the more rare species of soft coral are only suitable to advanced aquarists.  The genus Dendronepthya has coral species that are psychedelic cousins of the Kenya tree.  While they may look like vibrantly colored Capnella species, they are not. The species in this genus are non-photosynthetic, for the most part and are extremely difficult to rear.  If you intend to keep this species, be sure to have a ready and constant supply of phytoplankton (or culture your own phytoplankton), copepod larvae and rotifers and feed regularly.