Xenia

Scientific Name: Xenia elongata
Classification: Soft Coral
Common Names: Xenia, Pulsating Xenia

Description:
Pulsating Xenia has sturdy stalks up to 3" long which are tan in color. The end of the stalk is covered with a crown of feathery polyps, each carried on a stem approximately 1"-2" long. The polyps open and close in an attractive pulsing or pumping motion. Groups of these stalks form colonies that can spread into large mats. Xenia is one of the few corals that actually smells bad when removed from the water.

Natural Environment:
? Most specimens are captive grown

Care:
Hardiness: Xenia is an interesting family of coral as far as hardiness is concerned. Some hobbyist cannot seem to keep this coral alive and others find it to be a fast growing 'weed' coral. Although there are some guidelines which can be followed to improve the chance of success, no one fully understands what will guarantee success with this coral. Even a colony that has been thriving in a tank for an extended period of time can quickly go into decline and die for no obvious reason.

Lighting: Requires moderate to strong lighting. Usually, brighter is better although some hobbyist appear to have very good success with lower light levels.

Water Current: Xenia require at least moderate water flow. They are one of the few corals that seem content to be right against the strong output of a powerhead. In still waters the pumping usually diminishes and the coral goes into decline.

Temperature: Does well within a range of at least 75º to 83º F. Temperatures around 84º can sometimes appear to cause stress and Xenia appears to be more stable at lower temperatures of 76º - 78º.

Aggressiveness: Low. Xenia does not possess any apparent stinging capability and will not bother other corals, but can tend to grow over and shadow its neighbors. When happy, the coral can reproduce by division at an alarming rate and may require frequent pruning to keep it from crowding out other corals.

Feeding: Xenia is photosynthetic and does not accept any known foods. It is thought that they absorb some of their nutrients directly from the water. In fact, some hobbyist keep large colonies of Xenia as filter beds where the xenia is regularly pruned for nutrient export. It is unclear if this is very effective. Xenia may do better in tanks that are not heavily skimmed.

Supplements: The main supplement normally associated with successfully keeping Xenia is Iodine. Many authors state categorically that iodine supplements are critical to success and lack of iodine supplements will cause xenia to crash. I have keep Xenia with and without iodine supplementation and have observed no difference, so I am more skeptical of the iodine connection. Low Alkalinity levels can cause Xenia pulsing to decrease or cease altogether, so alkalinity levels should be monitored and kept above a minimum of 2.5meq/l.

Tank Positioning: Usually kept high up on the reef for strong water flow and highest possible lighting. Xenia will reproduce in the tank by attaching its stalk against adjacent surfaces it contacts and splitting into two colonies. In this way, Xenia colonies tend to 'walk' in the direction that water movement bends their stocks, so you may want to consider this in your placement. Xenia can usually be coaxed to grow up the back glass of the tank and forms a nice background display.