Pulsing Xenia Care Guide
Xenia umbellata is a pulsing soft coral whose polyps rhythmically open and close. It is photosynthetic, fast-growing and can spread aggressively in a reef tank.
Compiled by Aquairi from published sources · Published · Updated
Overview
Xenia umbellata is a pulsing soft coral of the family Xeniidae and the type species of the genus Xenia. It is unusual among corals for its rhythmic pulsing, in which the polyps repeatedly open and close their many-fingered hands to push water away from the colony. The form resembles a stalk topped with a bouquet of pulsing polyps. It is a fast-growing, photosynthetic coral popular in reef tanks.
Taxonomy
- Class: Octocorallia
- Family: Xeniidae
- Genus: Xenia
- Scientific name: Xenia umbellata Lamarck, 1816
- Note: type species of the genus (WoRMS, order Malacalcyonacea)
Habitat
The species occurs on Indo-Pacific and Red Sea reefs, where it has been recorded at sites such as Sharm el-Sheikh in Egypt. As a photosynthetic soft coral it depends on its symbiotic zooxanthellae for much of its nutrition.
Tank requirements
- Temperature: 24–26 °C (75–79 °F)
- pH: 8.1–8.4
- Specific gravity: 1.024–1.026
- Carbonate hardness (dKH): 8–11
- Calcium: 380–450 ppm
- Magnesium: 1280–1350 ppm
- Nitrate: below ~15 ppm; phosphate below ~0.1 ppm
- Lighting: medium, about 75–175 PAR
- Flow: low to moderate, indirect
- Minimum tank age: about 3 months
Moderate light and gentle, indirect flow encourage strong pulsing; flow that is too direct can interfere with the motion. Xenia often grows readily and does not require high-intensity light.
Diet
Xenia umbellata is mainly photosynthetic and meets most of its energy needs through its zooxanthellae, supplemented by absorbing dissolved nutrients; supplemental amino acids or phytoplankton may be offered but heavy feeding is unnecessary.
Compatibility
It is reef, fish and shrimp safe and lacks strong stinging tentacles, but it grows quickly and can overtake rockwork by spreading along stolons and releasing floating fragments, so growth control and placement on isolated rock are advisable.
Xenia umbellata Propagation Guide
Overview
Xenia umbellata is a pulsing soft coral in the family Xeniidae (genus established by Lamarck in 1816). It is a photosynthetic coral whose many-fingered polyps open and close in a constant grabbing motion that pushes water away from the colony, the behaviour behind the common name pulse coral. In the aquarium it is well known for spreading quickly across available surfaces.
Reproductive Mode
Xenia multiplies asexually with little intervention. A colony leans to touch nearby rock, attaches where it contacts, and the new stalk may separate from the parent to establish on its own, so the coral effectively walks and divides as it grows. This rapid, self-driven spread is why Xenia is often described as weedy.
Fragging / Asexual Propagation
To frag deliberately, snip a stalk near its base with sharp scissors or a clean blade, then loosely rubber-band the cutting to a rock or plug; it typically attaches on its own within a week or two. Including a small piece of rock helps the frag bond, since Xenia tends to slough off bare glue.
- Snip a stalk near the base with sharp scissors.
- Loosely band the cutting to a rock or plug.
- Place it in low flow and leave it undisturbed.
- It self-attaches within roughly one to two weeks.
Conditions for Propagation
Low flow and stable, established water favour both attachment and spread. To keep the rapid growth manageable, the colony is best started on an isolated rock or island so it can be contained and removed without overrunning slower neighbours.
Common Challenges
The main challenge is overgrowth rather than getting frags to take: Xenia can colonise the rockwork and crowd other corals, so regular pruning and physical isolation are the practical controls.