Yellow Sun Coral

The bright Yellow Sun Coral is another one of those… ‘knock-your-socks-off’ …beauties!

The pretty Yellow Sun Coral Tubastraea aurea is a nicely subdued color version of the Tubastraea genus. Another great photographic coral. The corallites of the T. aurea, the hard round, tubular structures that the polyps live in, are covered with a tissue called the coenosteum. The polyps have lightly colored tan or golden tentacles, with the center of the polyps being pale red-orange, and the coenosteum being yellow. It is similar to, yet a bit more delicate than, the slightly brighter Orange Sun Coral T. faulkneri, that has yellow polyps contrasted with bright orange centers and background.

Yellow Sun Corals extend their polyps tentacles mostly during the evening hours, though they can be coaxed out during the day if food is present. During the day the coral is completely withdrawn with only the yellow coenosteum being visible, making it look like a ball with raised round flat nubs. Other common names these corals are know for are Golden Cup Coral, Sun Coral, Sun Flower Coral, Tube Coral.

The Tubastraea genus can form colonies about the size of a fist in diameter. These will often grow on each other, forming a more complex and larger ‘community’. Some branch into 40″ (1 m) treelike structures. The Yellow Sun Coral can form colonies around 5″ (13 cm) in diameter. They are slow growers, only adding about 1.6″ of growth per year. The T. aurea are also ahermatypic, which means they don’t contribute to reef building.

Lighting has no affect on the growth of the Yellow Sun Coral. They are referred to as azooxanthellate, or non-photosynthetic corals. This means that, unlike most other large polyp stony (LPS) corals, they do not have a symbiotic relationship with the marine algae zooxanthellae. They survive in the wild with foods such as plankton they take from the water column. Some species also eat small fish. Like soft corals, the T. aurea can also produce bio-active compounds. Some of these can be damaging to the larvae of some corals, but one of these compounds, called tubastrine, has anti-viral properties.

The Yellow Sun Coral can be easy to moderate to care for. If you want a really easy coral that only needs to be fed a few times a week and is low maintenance, it is best to leave this coral alone. The T. aurea can be easy to care for if the correct husbandry is followed. Yet they can be very difficult for the aquarist who does not have the time for daily feedings, adequate filtration, and regular substantial water changes..

The T. aurea have a voracious appetite and will multiply for you if you can keep up with their feeding requirements. Light will not harm the Yellow Sun Coral, but they do not have a very good defense against algae. Algae grows fast in lit areas, and if algae is allowed to grow on the T. aurea, it will die eventually. Strong water movement is a must. Putting the coral in areas under ledges that usually do not have the water flow they need, can also cause algae growth.

Scientific name

Family: Dendrophylliidae
Species: Tubastraea aurea

Distribution / Background

Tubastraea Coral Information: The Tubastraea genus was described by Lesson in 1829. These corals are referred to as azooxanthellate or non-photosynthetic corals, which means they only survive with foods, and lighting has no affect on their growth. They are also mostly non-reef building corals, or ahermatypic.

There are 7 Tubastraea species. They are the Yellow Sun Coral or Golden Cup Coral T. aurea, Orange Cup Coral T. coccinea, Brown Cup Coral T. diaphana, Orange Sun Coral T. faulkneri, Floreana coral T. floreana, Black Sun Coral or Green Sun Coral T. micranthus (previously known as Dendrophyllia migrescens), and T. tagusensis. Some common names the Tubastraea species are known for are Orange Cup Coral, Brown Cup Coral, Pink Cup Coral, Rose Coral, Orange Polyp Coral, Black Tube Coral, Sun Coral, Black Sun Coral, Golden Cup Coral, Sun Flower Coral, Tube Coral, Green Cup Coral, and Black Branching Sun Coral.

The Yellow Sun Coral Tubastraea aurea was described by Quoy and Gaimard in 1833. They produce a bio-active compound with an anti-viral property called tubastrine. Some other common names these corals are know for are Golden Cup Coral, Sun Coral, Sun Flower Coral, Tube Coral.

Where Tubastraea Corals Are Found: The T. aurea are found in the Indo-Pacific; the Red Sea and western Indian Ocean to the southern Pacific.

Tubastraea Coral Habitat: The T. aurea inhabit the entrance of caves and underneath overhangs in waters that have a high nutrient content and strong water flow. Additionally, they have actually been found in sunlight, as well as areas not related to the reef. They are found at depths from 0 to 131 feet (0 – 40 m).

Status

The T. aurea is not on the IUCN Red List of Endangered Species.

Description

What do Tubastraea Corals look like: The Yellow Sun Coral is the most recognized of the Tubastraea genus. The T. aurea form colonies around 5″ (13 cm) in diameter, and sometimes will grow on each other, forming a more complex and larger “community.” It is a non-reef building coral, or ahermatypic. Their Corallites, or the hard round, tubular structure the polyp lives in, are covered with a tissue called the coenosteum.

The polyps tentacles of the Yellow Sun Coral are very fleshy, and extend mostly during evening hours, though they can be coaxed out during the day if food is present. The coral has tentacles that are a very lightly colored in an almost light fleshy color, or light golden with the coenosteum being yellow, and the very center of the polyps are a pale red-orange.

During the day the coral is completely withdrawn and only the yellow coenosteum is visible, making it look like a ball with raised round flat nubs. It is said these corals only grow 1.6″ a year (4 cm). Life span is unknown.

Difficulty of Care

Tubastraea Coral Care: The Tubastraea genus can be easy to moderate to care for depending on the dedication of the aquarist to feed the coral every day. Light will not harm them, but they do not have a very good defense against algae, which grows fast in lit areas. If algae is allowed to grow on the Yellow Sun Coral, it will die eventually. Putting the coral in areas under ledges that usually do not have the water flow they need can also cause algae growth. Strong water movement is a must.

Foods / Feeding

Tubastraea Coral Feeding: The Tubastraea genus are referred to as azooxanthellate, or non-photosynthetic corals. This means that, unlike most other large polyp stony (LPS) corals, they do not have a symbiotic relationship with the marine algae zooxanthellae. To feed they capture planktonic organisms, food particles from the water column, and can absorb dissolved organic matter. Some also eat small fish.

In captivity, the Yellow Sun Coral needs to be fed decent sized foods like enriched live or defrosted, or freeze dried adult brine shrimp, mysis shrimp, and other similar sized prey. Soak the food in a vitamin supplement, since that seems to help the coral reproduce faster. If they are well fed, they get a “bloated” look. Feed daily.

New colonies may need the juice of the shrimp wafting across the tops of their closed polyps for a few nights before they start to feed. Be patient and persistent since this can take up to 2 weeks. Feeding the same time each evening will get the best response. These corals will stop extending their tentacles and gradually waste away if they are not fed.

There are several ways to approach feeding your Tubastraea, so they can hold onto the food.

• One way is to take the coral out of the tank into a container with warm tank water (or float the container in the tank to keep it warm) and feed the polyps a high concentration of food. After the coral has fed, it can be put back into the tank, and the fouled container of water discarded. This option will help keep the water quality high. Remember to wiggle the coral so the polyps pull in before removing.
• The second way is to leave the coral in the tank. Put on a feeding “cap” to keep the food from blowing away, and also to keep shrimp and fish from taking the food out of the polyp’s mouth.
• The third choice is to simply turn off the pumps. But remember to turn them back on after they have fed.

Aquarium Care

Typical water changes of 20% a month, 10% biweekly, or 5% weekly are needed. It has been noted that 5% weekly water changes replenish many of the needed additives. Frequent water changes help to supply trace elements, but with higher concentrations of coral with calcareous skeletons, there may be a need put in additional additives to maintain proper levels for good growth. Trace minerals and iodine may be added

The following water supplements are suggested for Tubastraea species:

• Calcium: 380 to 430 ppm. If a large poly stony (LPS) coral does not have enough calcium, it will not grow. (Seachem makes a calcium additive that states 385 as sufficient)
• Alkalinity:3.5 MEQ/L (8 to 12 dKh, 10 is recommended)
• Phosphates: 0, zero. Phosphates are the worst of all and all corals hate them.
• Magnesium: 1200 – 1350 minimum. Magnesium makes calcium available, so if your calcium is low, check your magnesium levels before adding any more calcium.
• Strontium: 8 – 10

Aquarium Parameters

A well-feed live rock/reef environment is what is needed for your Yellow Sun Coral, along with some fish for organic matter production. A strong skimmer is recommended to take care of the nutrient load added by the heavy feedings needed for these corals. A mature tank is recommended.

Quick Reference Chart
Lighting:
Water Flow:
Temperament:

Be sure to have a strong water movement. Tubastraea species are tolerant of lighting in the aquarium. This is a peaceful species, but other corals may not be, so provide adequate space between species.

• Minimum Tank Size / Length:10 gallons (38 L) or larger
• Marine Lighting: Any
• Temperature: 74° – 83° F (23° – 28° C)
• Salinity / Specific Gravity: 1.023 – 1.025
• Water Movement: Strong
• Water Region: All areas of the aquarium, where it’s easy to feed

Compatibility and Social Behaviors

The T. aurea is peaceful towards other corals. However they do not have strong stinging tentacles, so need to be kept away from other corals. The only impact they will have on other corals is connected to their need to be fed large amounts of food, that may foul the water.

The Tubastraea genus is preyed upon by the Tubastrea Snail Epitonium billeeanum. These snails have a very similar color and shape as the coral’s polyps when closed. The nudibranch Phestilla melanobrachia is another pest. It comes in the color of the specific Tubastraea that it feeds on. Check your specimen closely when you get it, to find and remove these pests.

Sex – Sexual differences

Differences are unknown

Breeding and Reproduction

The large polyp stony (LPS) corals are hermaphrodites, male and female within the same organism, and can reproduce both sexually and asexually. In the wild they reproduce sexually by releasing eggs and sperm at the same time, resulting in a fertilized egg which then forms into a free-swimming planula larva.Eventually the planula larvae settles onto the substrate, becoming plankters. This then forms a tiny polyp which begins to excrete calcium carbonate and develops into a coral. Planula larvae are extremely vulnerable to predation, and very few survive. The Tubastraea genus can reproduce asexually as well through budding.

In captivity, propagating the T. aurea is done quite simply by breaking off pieces from a healthy colony. Another way is to keep the coral well fed with good water flow, and let it propagate by itself.

Potential Problems

Light will not harm the Tubastraea species, but they do not have a very good defense against algae. Algae grows fast in lit areas, and if algae is allowed to grow on the T. aurea, it will die eventually. Strong water movement is a must. Putting the coral in areas under ledges that usually do not have the water flow they need, can also cause algae growth.

The Tubastraea species have voracious appetites and must be fed regularly. These corals will stop extending their tentacles and gradually waste away if they are not fed.

Availability

Tubastraea Corals for Sale: The T. aurea may not be easy to find at pet shops and on line. They are usually just sold under “Tubastraea sp.” so you need to know their colors. The cost for online stores for Tubastraea sp. is around $35.00 USD or more depending on size and/or color.

References

• Animal-World References: Marine and Reef
• Anthony Calfo, Book of Coral Propagation, Volume 1 Edition 2: Reef Gardening for Aquarists, Reading Trees; 2nd edition, 2007
• Eric Borneman, Aquarium Corals : Selection, Husbandry, and Natural History , TFH Publications, 2001
• J.E.N. Veron, Corals of Australia and the Indo-Pacific , University of Hawaii Press; 2 Rev Ed edition, 1993
• Yellow Sun Coral, Tubastraea aurea, Microcosm Aquarium Explorer, Copyright 2008