Crazy for Caulastrea!

Posted by Quality Marine Staff on October 10, 2023

Crazy for Caulastrea! thumbnail image

The Candy Cane Coral, (Caulastrea furcata) goes by another common name as well – the trumpet coral. The scientific name of the genus Caluastrea is based in Latin, meaning stalked star. They are members of the family Merulinidae which includes a few other easily recognizable names such as: Favites, Goniastrea, Oulophyllia, Pectinia, Platygyra, and Trachyphyllia. This LPS (large polyp stony) coral easily shows why it earned this scientific name. The Candy Cane coral grows from a branching skeleton which continuously splits forming more and more “heads” or polyps at the tips. In the wild, and in aquariums if given enough time, these will form large colonies that almost appear as if they are one large connected piece of tissue. They are however all individually separate polyps only connected by the branching coral skeleton underneath. There are several different variations within Caluastrea – the most common being a reddish-brown crown with a neon green interior around the mouth of the polyp. Another popular variety is entirely neon green around the entire crown.

Caulastrea is a wide spread genus of coral, found throughout the Indo-Pacific region. While they are a photosynthetic coral – they can also consume food for energy, and therefore like to be found in areas that contain a lot of suspended foods. In the wild they are usually found forming large colonies – fields of Caulastrea that can go on for a long ways. The largest documented colony formed was over 16 feet wide in diameter! Found down to about a hundred feet in depth, they can also be seen in more shallow areas, like lagoons. If one was searching for Caulastrea in the wild it is usually slim pickings, until you find the one place where it has caught hold and the entire area seems to be dominated by it. It forms its own unique microbiome – usually in a place with sandy substrate, lots of suspended food in the form of fine plankton, and some degree of tidal flow to bring that plankton to them.

As far as keeping Caulastrea in captivity, it doesn’t require much and is a great choice for the beginner marine aquarist. They are very hardy, don’t require too much feeding in captivity – the clear water of our aquariums paired with modern lights generally give them everything they need. Some Caulastrea have even been kept in jar reefs – so there is no real minimum size aquarium for these corals. Parameters should be kept at reef levels – natural seawater strength or higher values for calcium, dkh, and trace elements. Depending on the collection point of your specimen water temperature values could vary quite a bit – the South Pacific provides Caulastrea for the trade and can reach as cool as 70 degrees Fahrenheit during the winter – but most specimens these days it seems are either aquacultured, maricultured or even broken off of large colonies growing happily in other aquarists tanks, where they can grow quite well! They can be kept happily with almost any standard reefing light fixture and should be given generous, but indirect flow. When in good condition the polyps at the end of the stalks will inflate and become puffy – while not a fast and hard rule, if your Caulastrea never becomes fleshy like this, it may be getting too much, or too direct flow. As far as displaying these corals go, they can either be mounted to a large plug, or a piece of rock work. In their natural environment they break fairly readily with branches falling down into sand nearby the colony allowing new colonies to start. The skeletal stalks wont be hurt by cutting them – so you can trim them or just push the stalk as is into your sand bed for a natural display. A tank completely filled with Caulastrea might be a stunning display – with a variety of small fishes living in and among it!

These corals aren’t the easiest to feed, despite their hardiness. When the circumstances are right they will have small feeder tentacles at the center of each polyp surrounding their mouth. If you ever see this, reduce flow and target feed the polyps with a fine plankton type mixture. Larger polyps can maybe be offered finely chopped meaty foods like mysis shrimp turned into a paste – but don’t push it as anything too big will take too long for them to eat and might encourage fish or invertebrates to come and pick at those polyps – not only robbing them of a meal, but also potentially harming them in the process. As with almost everything in the hobby, take time and observe. Corals also usually seem to get used to a feeding pattern and can “learn” to be more aggressive feeders over time. Start small, and work your way up. These guys do appreciate food as some of the areas that they are collected in are almost turbid; living in nutrient rich water that is moving with lots of suspended food particles. Give your coral some time to settle into its new home, and if you aren’t seeing it extend feeder tentacles when other corals are being fed you may have too much flow during feeding.

While we are unaware of any cases of Caulastrea reproducing sexually in the aquarium, in the wild they will release eggs and sperm simultaneously, so that the fertilized eggs can drift with the current and establish new stands of Caulastrea elsewhere. In general, the colony grows through budding, where polyps essentially form new polyps which will start growing off onto their own stalk and eventually become entirely separate stalks and polyps (referred to as stars or crowns in this article).

Fragmentation is when some of these stalks break, isolating some polyps from the rest of the colony. These will continue to expand through budding as long as there is one healthy polyp remaining after the fragmentation occurs. This is what is referred to as “fragging” in the aquarium industry; essentially you are taking bone cutters or an appropriate saw and using it to fragment some polyps from the rest of the colony, but beware – just about the only issue that can occur here is if two polyps are still somewhat attached in the process of budding. These can tear apart when you separate the stalks and that is an open wound for infection or other issues. So when fragging try to select stalks that are completely separated from their neighbors. Growing and fragging this coral is one of the easiest in the hobby – you can usually break apart stalks with fairly little effort with your bare hands – and no need to go further, just like in the wild these “frags” can just have their stalk stuck in the sand and you can either grow a new separate colony or perhaps trade this coral with other hobbyists or your local fish store!

Caulastrea is the right choice for almost any reef aquarist so long as they have a healthy aquarium of any size and the right parameters and lighting to maintain and grow coral. If you’re looking for your first stony coral to grow and culture – it would be hard to pick a better one. So what are you waiting for? Call or visit your local fish store today and ask them to source you some sustainable Caulastrea from Quality Marine today!