A good read for those keeping sun coral.

[allantang]

http://www.marineaquariumsa.com/showthread.php?t=17421

[Harlequinmania]

Great article . thanks for sharing

[jackywongto]

thanks for sharing Allantang

One of my favorite coral. It adds very nice coloration to the tank. MarineLife Henry has some nice colonies in his display tank. The only negative side is that you need to either flood your tank with food or target feed them regularly.

Copying and pasting here for the convenience of everyone.

Taken from http://www.ultimatereef.net/forums/s...d.php?t=195870

Everything you want to know… Almost

Introduction

Family: Dendrophylliidae

Genus: Tubastraea (Latin: Tubus (Tube) Astron (Star))

Species: Tubastraea aurea (Quoy and Gaimard, 1833)

Tubastraea coccinea (Lesson, 1829)

Tubastraea diaphana (Dana, 1846)

Tubastraea faulkneri (Wells, 1982)

Tubastraea floreana (Wells, 1982)

Tubastraea micrantha (Ehrenberg, 1834)

Tubastraea tagusensis (Wells, 1982)

Tubastraea tenuilamellosa (Edwards and Haime, 1848)

Common Names: Orange / Black (T. micrantha, T. diaphana) / Yellow / Green (T. micrantha, T. diaphana) / Red /Sun coral, Cup coral, Tube Star, Black Turret Coral (T. micrantha, T. diaphana), Tree Coral(T. micrantha), Sunflower coral, Sun polyps, Tube coral, Daisy coral, Octopus coral (T. micrantha, T. diaphana), Cave Coral.

Distribution: Australia, British Indian Ocean Territory, Cape Verde, Comoros, Djibouti, Egypt, Fiji, Hong Kong, China, India, Indonesia, Israel , Japan, Kenya, Korea, Madagascar , Malaysia, Sabah, Maldives, Mauritius : Rodrigues, Mozambique, Palau, Philippines, Saudi Arabia, Seychelles, Singapore, South Africa, Sudan, Taiwan, Province of China, Tonga, Brazil, Hawaii, Galápagos Islands.

Profile

Tubastraea is a non-Zooxanthellae coral of the family Dendrophylliidae which inhabits overhangs, vertical surfaces, cave entrances, and in some instances the open reef. The reported depth range for Tubastraea spp. is 3–7 m (Wells, 1982), but it has also been observed at a depths of 15m (Esther G.L. Koh, Hugh Sweatman), and 25m (Arthur G. Humes).

Tubastraea sp. are thought to be ahermatypic (non-reef building), but this classification is under going reappraisal, largely due to the growth rate and size of T. micrantha.Despite the low calcification rate of T. micrantha, the linear skeletal extension, in the form of arboreal type branches, is nothing short of rapid for a Azooxanthellae (does not contain Zooxanthellae) species. This rate of growth is directly comparable to the rates shown by many symbiotic, hermatypic (reef building) corals.

To further call into question the ahermatypic classification; Tubastraea micrantha possesses one of the densest calcium carbonate skeletons amongst the order Scleractinia, and as testament to the skeletal strength and tenacity of these animals, the "Black Sun Coral" was one of the few species of coral remaining on the Atoll reefs after the nuclear weapons testing, performed in the Pacific by the Americans in the 1960's.

Although the typical colours for Tubastraea polyps are yellow through to orange; the range of polyp colours seen within nature and the aquaria (to a lesser agree) can be staggering such as green, brown, or white in the case of T. micrantha. The spectacular diversity of colours is evident with-in the images below.

Tubastraea is a non photosynthetic coral, and as such, does not contain unicellular photosynthetic Zooxanthellae symbiants. Species from this genus do not require exposure to sunlight or specific lighting (within the aquaria) for the purposes of photosynthesis. That said, Tubastraea spp. can and will tolerate varying light intensities. This is evident in nature by the coexistence and persistence of the non-symbiotic, Tubastraea Micrantha, on the open reefs amongst the Western Caroline Islands (Republic of Belau).

Tubastraea Anatomy

Images: Authors own

Corallite: The skeletal material produced by a single polyp

Calice (pl. calices): A concave depression the “end” of the corallite that houses the polyp

Septum (pl. speta): These are skeletal plates that radiate into the calice from the theca (the corallite wall). The Septum is also sometimes referred to as; scleroseptum

Coenosteum (pl. coenostea): The skeletal material between walls of adjacent corallites.

Coenosarc: The fleshy / skin type tissue covering coenostea and corallites.

Tentacle: A nematocyst-laden appendage used to capture prey, and also for defence / offence.

###### disc: The broad area of tissue between the mouth and polyp tentacles.

Mouth: The mouth is a sphincter (ring of muscle) that open and closes to allow passage of food / waste to and from the Gastro Vascular cavity.

Gastro vascular cavity: The gut of the polyp.

Mesenterial filaments: The Gastro vascular cavity is divided into sections by these muscular “curtains” of tissue, which are used for digestion and polyp retraction / extension.

Feeding Methods and Handling

Due to the lack of Zooxanthellae, Tubastraea spp. MUST be fed by the aquarist between 2-7 times a week to maintain health and growth, for Tubastraea micrantha daily feeding is required. **This is not a coral for the lazy**. It is believed that each polyp must be individually fed on meaty offerings such as vitamin enriched brine / Mysis shrimp and krill along with other foods along the lines of, chopped mussel, squid, Cyclop-eze™, etc. It is believed that using live Brine shrimp as a part of the corals diet will increase the intensity of the coral colour, especially in the case of orange / yellow specimens.

When choosing a "sun coral" at a local fish shop, it is desirable to look for a specimen that is already feeding and shows little sign of starvation. A feeding specimen can be recognised as it will look puffed up or plump, especially after food is placed in the tank. Consider asking your local stockist to add some food to the corals holding tank, or ask what time they normally feed the coral, and if you can be present.

The tell-tale signs of an under-fed or malnourished animal are relatively easy to spot; such as clearly showing calices (cups), the coenosarc (flesh / skin) covering the cups will also appear to be extremely thin and taut. The presence of excessive algae growth may sometimes indicate a possible weakness. If your specimen already has algae present then every effort should be made to carefully remove the intrusion without causing damage.

After transportation and acclimatisation, a newly acquired sun coral may-be reluctant to expand its tentacles in preparation for feeding. These tentacles are used to capture and incapacitate prey which range in size from planktonic forms to small fish. One way of coaxing the polyps to expand and open, is to very gently waft / blow a small amount of brine shrimp juice, Phyto-plankton, Cyclop-eze™, or, Coral Vibrance™ over the cups of the coral.

Images courtesy of: Steve Margetts

If, after several days and nights (sometimes a couple of weeks) of "wafting"the polyps still fail to show any sign of opening, its possible that the coral may no longer have sufficient energy remaining to expand, as a result the slow process of starvation will begin, along with tissue thinning and recession, eventually leading to death.

What is meant by, “sufficient energy remaining”? What the author is referring to is stored Nitrogen and Phosphorous within the coral skeletal body. In the absence of food the coral can use the ‘store’ to sustain life for a number of weeks if the coral was in good health prior to harvesting, etc. Unfortunately with some corals the process of actually getting to a reefers system is a drawn out stressful affair, and often goes without any food from harvest to purchase.

Interestingly, although it is commonly thought that each polyp of the colony is a separate animal, and as such do not share ingested nutrients, the ‘back-up energy’ supply is a common store held with in the porous skeleton for the good of the entire colony.

On a brighter note, it’s not all doom and gloom. Once Tubastraea is accepting your meaty offerings and the feeding regime is maintained, it’s a hardy inhabitant that will reward you with a daily stunning display of large, usually intensely coloured polyps, and in time daughter colonies within the aquarium (see, reproduction).

Once the coral is opening enough for you to feed, there are various methods of delivering food stuffs to the polyps that can be employed.

If the coral is to be fed within the aquarium, the simplest means is to use a syringe or turkey baster to deliver foods such as Mysis, and Artemia to the ###### disc and tentacles of the polyp. Care must be taken during this process, if the food is released with to much pressure or the polyp is “poked”, it will contract and you’ll be unable to fed, until it re-expands.

When feeding within the aquarium, the food offered to the coral may be “stolen” by shrimps, who will actually remove the food from the gut of the coral. One method of combating this is to cover the coral will half a fizzy drinks bottle or similar, this is sometimes known as the “top hat” method. Another method of fending off unwanted visitors is to “guard” the coral with an acrylic rod; this method is preferred where the colonies are too large when expanded to be contained within the “top hat”.

An alternative method to feed this wonderful animal is to remove the coral from the aquaria in a suitably sized container. To carry out this procedure it is necessary to submerge the container, pick the coral up by its underside (scoop it up with an open hand) and place within the container, ensuring complete water coverage of the coral during removal always allowing for polyp expansion. Once the polyps have expanded, feeding can commence with your chosen foods. Once the coral has moved the food down to its gut, it may be returned to the aquarium by reversal of the above procedure. In the author’s opinion, this method should not be your first choice. Constant handling may cause stress and damage to the coral.

When handling the coral, great care must be taken as, although the main skeletal body is strong, the coenosarc, corallites and calices are fragile and easily damaged. Under no circumstances should the coral be removed from the water and exposed to the air if the polyps are extended. The result of such action can be torn tissue around the calice edge which, in some instances may be irreparable.

When feeding Tubastraea, it is important to remember that it is very easy to increase the NO3 (Nitrates), PO4 (Phosphates) and dissolved organics within the system due to the regurgitation of food (if it had eyes, they'd definitely be bigger than its belly), and food that "escapes" the polyps un-checked whilst feeding within the aquarium. There are many ways around this problem; ample detritus eaters or scavengers amongst the clean-up crew, heavy skimming and high flow, “algae scrubber” sumps, removing uneaten food, removing the coral for feeding (note: doesn’t help with regurgitation), regular water changes, and of course, only feeding little and often.

The Captive Environment

As with all Stony corals, algae cover, NO3 and PO4 are detrimental to the health of Tubastraea colonies. Water parameters in the range of 24-28°C, Specific Gravity 1.024-1.026, pH 8.1-8.4, dKH 8-10 would ideally be adhered to for continued health. Excessively high dKH, PO4 and / or NO3 can lead to rapid recession of the coenosarc.

Poor water quality, namely high nitrates and poor levels of dissolved oxygen, can lead to the coral failing to expand and may lead to a possible event called ‘polyp bail-out’. This is where a polyp exits its calcium carbonate cup and becomes free swimming. In nature, when a polyp bails out, it will seek a “better” location and settle upon a rock or similar, to begin laying down a new corallite and in time a form new colony.

If the bail-out occurs in the home aquaria the polyp will unfortunately fail to survive, due to being unable to find “cleaner”, more oxygen rich areas.

As mentioned previously, Tubastraea spp. are a part of the family Dendrophylliidae and do not contain Zooxanthellae and do not require light for the purpose of photosynthesis. That said, it doesn’t mean that the aquarist has to place his / her prize Tubastraea in a cave or under a ledge. The prevalent “myths” which state that Tubastraea sp. are found in caves and overhangs, because their in-tolerant to light, is a complete fabrication. The reason these corals are found in such areas is because of nutrient levels. Caves and overhangs etc are naturally rich gathering areas for zooplankton and other small food sources, and is possibly the sole reason for the presence of Tubastraea.

If acclimatised to avoid possible UV “burning”, Sun Corals will tolerate moderate to strong light. As an example, Tubastraea micrantha, as mentioned previously, are commonly found on open reefs amongst light demanding stony coral species such as Acropora sp.

**Warning** If you are going to place the coral in moderate to strong light, remember that you increase the risk of algae growth upon the coral, especially if the coenosarc has receded between the corallites exposing the coenosteum. Another important point to remember when picking a location for the coral in the aquarium is; Above all, make sure that you can get to the coral for easy feeding.

Tubastraea sp. prefers an alternating, moderate (to strong, for T. micrantha and T. diaphana ) water movement, which will also serve to keep the coral free from detritus build up. Heavy protein skimming will aid water quality and help keep the levels of dissolved organics low within the reef aquaria, which are easily elevated when feeding a coral regularly. If detritus does build up between the corallites and is not removed, the coral may become smothered by cyanobacterial algae (Oscillatoria spp.), which, if left unchecked, will destroy the coenosarc lying underneath.

Reproduction

Tubastraea sp. are know to reproduce by the means of Gametes (sperm and eggs), egg – sperm packets / bundles, brooded planulae larvae (free swimming larvae), budding and polyp division. If well-fed and kept in good health, colonies will readily reproduce in their captive environments.

Both T. faulkneri and T. coccinea are reported to be hermaphroditic (each mature colony contains both male and female reproductive structures) and can reproduce by the means of planulae larvae, budding and division.

Planulae larvae is produced when a male polyp is triggered into releasing sperm, by chemical ‘messages’ given out by a female polyp. This sperm then swims into the female where it meets ‘her’ egg and the process of internal fertilisation begins.

The resulting larva is formed with-in the female (known as brooding) and when developed its released from the polyp and becomes free swimming. When the larvae, which is approximately 1.6mm long, settles upon a rock, etc, it will quickly turn into a tiny polyp (or two) and begin laying down a new skeleton. From this point the polyp is able to bud and divide, thus creating an entirely new colony.

Image: Daniela Stettler

The above image shows a mature T. coccinea polyp releasing planulae larvae.

It is possible to identify whether the settled larva was spawned by T. faulkneri or T. coccinea, by the amount of polyps the larva develops into. A newly settled larva from faulkneri normally develops two polyps, where coccinea will develop a single polyp.

Images: Authors own

The above image shows some T. coccinea ‘offspring’, and a size comparison against a Copepod.

It is also possible for a new colony to establish though budding alone. A newly formed bud can brake away from the ‘mother’ tissue and either float or crawl across rock / substrate to a new settlement point.

Tubastraea aurea is believed to be a gonochoric coral (male and female reproductive structures are in separate male and female colonies) and as such, it breeds via the release of gametes. As with other gonochoric corals, IE Acropora sp, the release of sperm from the males and eggs from the females is synchronised using the phases of the moon and the resulting temperature variations. Once the egg has been externally fertilised, a larvae is developed…

Tubastraea micrantha and Tubastraea diaphana are reported to be a ‘brooders’, and reproduce in the same manner as T. faulkneri and T. coccinea.

In fact Tubastraea aurea appears to break the generalisation that all members of the family Dendrophylliidae are ‘brooding’ corals.

references:

Roger Hughes

Ultimate Reef

[allantang]

Hope all sun lovers will benefit from the sharing.

Jacky how did u copy n paste? I tried doing it but end up with pictures disappearing.

[allantang]

Btw, Jacky. Don't get sun burn! Haha

[poomoon]

thanks, great read !