Tubastrea coccina, aurea, faulkerni, micrantha (Sun Polyps) : Let The Sun Shine In!!!

by

Mark McDowell, Ph.D.



Sun Polyps!!!

This coral is one of the most beautiful corals in the home aquarium today. Sun polyps are abundant in the West Indies and the Bahamas near the surface to 35 meters depth. They also occur in western Africa and are frequently imported from the Indo-Pacific. The Tubastrea corals are members of the Dendrophyllidae family, which means they lack zooxanthellae and the ability to produce their own food via photosynthesis as most corals can do. Translated in normal reef terms, they need to be fed and fed quite often in order to thrive. The most common color is orange and red, but on occasion the yellow and black variety become available. The polyps often form little individual mounds with tissue covering a skeleton that the polyps extend from. Individual colonies may range from a few polyps to several hundred. They have twelve large septa of equal size with several smaller septa between and a slit or mouth in the center that is usually surrounded by a dark region.

Sun polyps inhabit shady areas and caves in the wild where they don't have to compete for survival with photosynthetic corals in order to thrive. It is widely published that the Tubastrea coral needs to be place in the dark or in a shaded area. Well, I am going to disagree with that and say that it really does not matter where you place them in the home aquarium. As long as they are getting regular feedings, they could care less about the light. I think the reason for the dark references is more to keep unwanted algae growth off of them when they close up. I have my sun polyps right on top of my tank using power compact lights and they open up whenever I feed them no matter what time of day it is.

They require frequent feeding when their tentacles are extended. Though sun polyps have a calcareous skeleton, they are not reef building corals. They require moderate to strong water current and can easily be overtaken by algae. They must be feed at least twice a week but every other day is preferred. They reproduce by releasing free-swimming planula larvae into the water and the adult usually dies shortly thereafter. The larvae swim around in the aquarium for 2 to 4 days, then settle down on a suitable surface. After a few months, numerous lentil-sized miniature colonies are an indicator of successful reproduction. They are extremely sensitive to nitrates so nitrate levels must be kept to a minimum. This seems like a contradiction since they require frequent feeding which can elevate your nitrate levels. Therefore, an efficient protein skimmer is a must as well as efficient biological filtration.

I have four colonies of sun polyps, two orange, one red, and one yellow. These polyps have been growing very rapidly and spreading over the entire rock surface. None of my polyps were full skeletons when I purchased them and the yellow ones only had 5 polyps and in six months, has grown to over 20.

I feed my sun polyps a mixture of frozen brine shrimp and marine cuisine cubes in order to entice them to come out. This is done by putting the cube in the tank directly over them and placing the cube between my index and thumb and letting it dissolve over the polyps. The polyps soon open up and I then take frozen krill and crush it between my two fingers over them until all of the polyps have had a piece or two. The whole feeding process takes less than 15 minutes. Of course the fish in the tank rush over to get a quick meal, but they do not eat all of the food since I put krill on two sides of the tank at one time. One piece over the polyps and another piece on the opposite side of the tank to serve as a decoy for the fish. They get confused as to which side to go on and the polyps benefit from their confusion.


Sun Polyps Closed   


Sun Polyps starting to open


Sun Polyps fully open

                                                  

When sun polyps are first introduced to your tank they may not come out at all. It is important to feed them and get the polyps to open as soon a possible. I always take a small bucket and fill it with aquarium water, place the coral in it and put a frozen brine shrimp or marine cuisine cube in it and let it stand for 20-30 minutes. This may have to be done everyday for a week or so in order to get the polyps to come out and feed. Once the polyps take less than five minutes to expand and feed, then you can start feeding them in your main tank since they are used to coming out to feed in such a short time. The key is to minimize the amount of food that you have to place in your tank in order to cut down on the organic waste.

I have four colonies of sun polyps, two orange, one red, and one yellow. These polyps have been growing very rapidly and spreading over the entire rock surface. None of my polyps were full skeletons when I purchased them and the yellow ones only had 5 polyps and in six months, has grown to over 20.

This coral is definitely not for the beginning hobbyist or for an aquarium with minimal protein skimming. They require extra TLC and should not be purchased if you do not have the time or patience to take care of them. If you are interested in the Tubastrea species of coral, you should be aware of the special requirements and be patient, they will be very rewarding and look like a bright orange bouquet of flowers once they are acclimated to your tank conditions. They may look like a dull orange ball, but when they expand, they are one of the most beautiful corals in the world!!!


References:

Paul Human, Reef Coral Identification (Florida, Caribbean, Bahamas), 1993, pg. 164-165.

Dr. P. V. Loiselle and Hans A. Baensch, Marine Aquarium Manual Comprehensive Edition,1991, pg. 143-144.

Dr. Patrick L. Colin, Marine Invertebrates And Plants Of The Living Reef, 1978, pg.291-294.

Martin A. Moe Jr., The Marine Aquarium Reference - Systems And Invertebrates, 1989, pg. 440.

Ed Puterbaugh and Eric Borneman, A Practical Guide To Corals For The Reef Aquarium, 1996, pg. 43.


Copyright © 2000 Mark McDowell, Ph.D. All rights reserved