The Finger Leather Coral Alcyonium sp. makes a great beginner soft coral. Warm or cool water, bright to low light, these corals accept a wide variety of environments, depending on the species you may want. The Alcyonium genus has species that are found in subtropical, temperate, and warm waters. Basically they are found worldwide, and the bonus is they are easy to care for.
As with all soft coral however, identifying this genus can be confusing, even to experts. These corals have been divided into more and more genus categories as time goes on. For example, the Alcyonium genus was once joined with the Cladiella, which is a similar genus. Also another species, Parerythropodium fulvum fulvum was at one point thought to be part of the Alcyonium genus. Indeed, in some cases the distinctions can only be determined by microscopic examination.
The Alcyonium species grow upright with or without a stalk, yet colonies are small. They have a widely variable growth pattern, but are most often encrusting and lobate. Lobate means they form several roundish, flattish short projections that are separated by a gap or fissure. Yet they can have finger like or globular projections as well, contributing to the mass confusion of these corals. Their color is usually pale brown, dark brown, or gray; but colors can be yellow, green, red, and orange, or a variety of hues within these colors. The polyps can be the same color or a contrasting color of the main body.
Although they are part of the leather coral family Alcyoniidae, the Finger Leather Corals Alcyonium sp. differ from other Leather Corals because they are slimy to touch rather than leathery. Therefore we have included them in with the Soft Corals. Some common names these corals are known for are Finger Leather Coral, Dead Man’s Finger Coral, Chili Pepper Coral, Encrusting Leather Coral, Bushy Soft Coral, Seaman’s Hand Coral, Yellow Bush Coral, and at times, when there is an unidentified coral, it is called a Colt Coral.
The Alcyonium genus is very easy to care for and can be recommended for beginners. Just make sure you get the species you want. Cold water species must be provided with a cool water environment, which will mean having a chiller for the reef aquarium system. Don’t mistakenly get a cold water species for a normal tropical reef tank, or it will die in that environment in about 2 weeks. You can also wait at least that long to see how it is doing before buying.
To learn about different types of soft corals, see:
Soft Coral Facts
- Kingdom: Animalia
- Phylum: Cnidaria
- Class: Anthozoa
- Order: Alcyonacea
- Family: Alcyoniidae
- Genus: Alcyonium
- Species: sp.
Distribution / Background
Soft Coral Information: The Alcyonium genus was described by de Blainville in 1930. There are quite a number of species currently ascribed to this genus, about 50 or so. Some of the more common species include A. complanatum, A. digitatum, A. fulvum, A. molle, A. sidereum, A. aurantiacum, A. gelatinosum, A. glomeratum, A. palmatum, A. pulmonaria, A. rudyi, and A. schlosseri.
Some common names the Alcyonium corals are known for are are Finger Leather Coral, Dead Man’s Finger Coral, Chili Pepper Coral, Encrusting Leather Coral, Bushy Soft Coral, Seaman’s Hand Coral, Yellow Bush Coral, and at times, when there is an unidentified coral, it is called a Colt Coral. The Alcyonium genus has been propagated in captivity.
As with all soft coral, identifying this genus can be confusing even to experts. These corals have been divided into more and more genus categories as time goes on. For example, the Alcyonium genus was once joined with the Cladiella genus. The species Parerythropodium fulvum fulvum was at one point thought to be part of the Alcyonium genus.
Where Alcyonium Corals Are Found: The Alcyonium genus are found in the warm tropical waters of the Indo-Pacific and the cold waters of the North Sea, Atlantic Ocean, British Isles, and the Mediterranean.
Alcyonium Coral Habitat: The Alcyonium genus are found in calm, yet turbid waters from depths of 10 to 130 feet (3 – 40 m).
What do Alcyonium Corals look like: The Alcyonium genus grows upright with or without a stalk, yet colonies are small. They have a widely variable growth pattern, but the Alcyonium genus is most often encrusting and lobate, which means they form several roundish, flattish short projections that are separated by a gap or fissure. They can have finger like or globular projections as well, contributing the the mass confusion of these corals!
These corals are completely an autozooid type, which means all of their polyps are used for feeding, and none for movement of water. They grow to about 6″ (15 cm) tall. Their colors can be yellow, green, red, orange, brown, or a variety of hues within these colors. The polyps be the same color or a contrasting color of the main body, such as brown, pinkish white, white, etc.
Difficulty of Care
Soft Coral Care: The tropical Finger Leather Coral Alcyonium sp. is very easy to care for and can be recommended for beginners. Their only requirements are a low to average water flow and moderate lighting. A. digitatum, A. glomeratum, A. hibenicum, and A. palmatum are all cold water species. If kept in a typical tropical aquarium, they will die within a few weeks. They must be provided with a cool water environment, which will mean having a chiller for the reef aquarium system.
Foods / Feeding
Soft Coral Feeding: In the wild, Alcyonium corals have developed several feeding strategies. They capture microscopic food particles from the water column and can absorb dissolved organic matter. Those most commonly seen in the aquarium trade have a symbiotic relationship with a marine algae known as zooxanthellae, where they also receive some of their nutrients. These are photosynthetic. Deep water species and those from temperate climates may not have this symbiotic relationship. These types, known as aposymbiotic, do not receive nutrition from this source.
In captivity, depending on the species, they only eat only phytoplankton or zooplankton. You may test your specimen and make a determination. Feed accordingly. According to one study, A. siderium is known to capture and eat brine shrimp in the wild.
Stable tank conditions are needed to keep the Alcyonium genus. Doing water changes of 20% a month or 10% biweekly is needed, although it is suggested that doing 5% water changes once a week will replenish many of the needed additives. Calcium and other trace elements can be added to maintain proper levels for good growth.
Suggested levels for Alcyonium species are:
- Calcium: 400 – 450 ppm
- Alkalinity: 3.2 – 4.8 MEQ/L (8 to 11 dKh – 10 is recommended)
- Phosphates: 0, zero.
- Magnesium: 1200 – 1350 ppm. (Magnesium makes calcium available, so if your calcium is low, check your magnesium levels before adding any more calcium.)
- Strontium: 8 – 10
|Quick Reference Chart|
A typical live rock/reef environment is what is needed for your Finger Leather Coral, along with some fish for organic matter production. Most Alcyonium sp. commonly available are tropical corals. If you obtain a cold water species, they must be provided with a cool water environment which will mean having a chiller for the reef aquarium system.
Provide proper lighting and water movement. A low to average water flow and moderate lighting is what is needed. Finger Leather Corals are peaceful toward other soft corals.
- Minimum Tank Size / Length:
Warm water species: 50 gallon (190 L) or larger
Cold water species: 10 gallon (38 L) or larger
- Marine Lighting:Warm water species: Moderate
Cold water species: Any
- Temperature:Warm water species: 78° – 84° F (25° – 29° C)
Cold water species: 40° – 39° F (4° – 15° C)
- Salinity / Specific Gravity: 1.023 – 1.025
- Water Movement: Low
- Water Region: Bottom of the aquarium
Compatibility and Social Behaviors
Sex – Sexual differences
Breeding and Reproduction
The Alcyonium genus, depending on species, may release gametes into the water annually. This is true of A. digitatum, which is a temperate species while A. hibernicum has sort of an internal brooding going on. Like other soft corals, the Alcyonium genus may also use several different forms of reproduction such as fission, fragmenting and/or branch dropping.
To propagate your Finger Leather Coral, first make sure it is healthy.
- Small Frag:
To frag a small piece you may use a pair of very sharp scissors or a scalpel. Just simply cut a small forked frag away from the mother colony while still in the tank. (1-2″ frag size). Loosely rubber band the frag between branches and affix it to a small piece of rubble that has a natural indent or a plug.
- Large Frag:
For larger fragging, the Finger Leather Coral should have all polyps retracted before proceeding. Remove the coral from the tank and quickly perform the fragmentation from a mother colony with a clean razor, scalpel, or knife. (Scissors can damage tissue from larger fragging cuts.) The frag can be glued, tied, sewn to a rock or plug, or just set on rubble where the current will not take them away, but will help them heal.
Provide a bath of clean temperature and salinity adjusted water (same as main tank) with a little iodine before returning to the tank. This bath will help clear out the mucous that the leather will produce from this procedure.
Return the Finger Leather Coral to the same spot it was in before fragging and discard bath water. Placement will depend on the size and shape of the frag. But at the very minimum place it close to where the mother colony is located, perhaps using the mother colony to block a water flow that is too quick for the frag.
With both procedures, the coral will more than likely deflate. With good water flow it will recover. Corals can emit nasty and at times noxious odor, so be sure there is good ventilation. Clean up any mucous when finished to prevent any possible health problems.
The Alcyonium genus is hardy and very easy to care for. However coral diseases are commonly caused by stress, shock (like pouring freshwater into the tank and it coming in contact with the coral), and incompatible tank mates including specific fish, or pests. Here are treatment suggestions for some ailments:
- Flatworms, brown jelly infections, and cyanobacteria:
Treat with a freshwater dip of 1 to 3 minutes with chlorine free freshwater of the same temperature and PH as the main display.
- Cyanobacteria and brown jelly infections:
These can also be treated with Neomycin sulfite, Kanamycin and other broad-spectrum antibiotics. The pill can be pulverized into a fine powder, mixed with sea water to make a paste, and then applied to the wound, or affected site of the coral with a simple artists brush.
- To prevent necrosis, and fight black band disease:
The corals can be treated with Tetracycline at 10 mg per quart/liter according to one author.
Other cures include lugol’s dips at 5-10 drops of 5% Lugol’s solution per quart/liter of newly mixed sea water that has been mixing for 10-20 minutes. Start with a 10 minute dip and observe the reaction of the coral. A daily dip can be done until the coral is cured.
- Procedure that can save a coral’s life if nothing else is working:
Amputation of the affected area. This must be done in a separate container consisting of some of the tank’s water. Cut slightly into healthy tissue surrounding the diseased flesh then reattach the coral to the substrate with the open wound cemented on part of the reef structure. For wound that are on the side or top, some have used “liquid band aid” or super glue to seal the wound.
- Animal-World References: Marine and Reef
- Eric Borneman, Aquarium Corals : Selection, Husbandry, and Natural History , TFH Publications, 2001
- Anthony Calfo, Book of Coral Propagation, Volume 1 Edition 2: Reef Gardening for Aquarists, Reading Trees; 2nd edition, 2007
- Harry Erhardt and Horst Moosleitner, Marine Atlas Volume 2, Invertebrates (Baensch Marine Atlas), Mergus Verlag GmbH, Revised edition, 2005
- Ronald L. Shimek, Guide to Marine Invertebrates: 500+ Essential-to-Know Aquarium Species, Microcosm, 2005
- Mark R. Patternson, Patterns of Whole Colony Prey Capture in the Octocoral, Alcyonium siderium, American Society of Ichthyologists and Herpetologists, Copyright ©2000-2010 JSTOR
- Y. Benayuahu and Y. Loya, Sexual Reproduction of a Soft Coral: Synchronous and Brief Annual Spawning of Sarcophyton glaucum, American Society of Ichthyologists and Herpetologists, Copyright ©2000-2010 JSTOR
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