The Sun Coral is an awesome and popular large polyp stony corals (LPS coral) that is often sought after in the aquarium hobby, because of their bright orange-yellow, “sunny” polyps. There are more than just one species of suncoral out there, so you may sometimes see them listed as Tubastraea, which is their genus.
A genus is a scientific classification that organizes a group of similar species together. If you take one look at them, you totally understand the name. The polyps are round, fleshy, and bright yell0w and orange and look a bit like the sun. What is remarkably ironic about these beautiful invertebrates is that they are non-photosynthetic, which means they don’t get any of their nutrition from the light of the sun, or in your case, from your reef tank lights.
That makes them a bit more challenging to keep in a home aquarium because they are totally dependent on you feeding them, which creates its own complexities. Since they don’t need light, this Tubastraea species is a perfect coral to add to those dark and marginal areas of your tank, to add a burst of color to the otherwise dim spots in your aquarium.
In the ocean
Sun corals are usually found in tropical and subtropical rocky and coral reefs all across the world’s oceans and seas. They are most commonly spotted in deeply shaded areas such as crevices, pier pilings or caves. They also build their colonies on artificial surfaces like pillars or shipwrecks.
While all coral polyps are dependent on the flow of the ocean to bring dinner to them, the sun coral, being non-photosynthetic, is completely dependent on capturing food to survive, unable to get a free meal from commensal zooxanthellae.
Sun coral care
Most people who have kept Tubastraea corals in their tanks would say this is a moderately difficult species. Unfortunately, some newer, relatively less-experienced aquarium-keepers have had trouble getting them to open up and accept foods.
Sun corals are not aggressive and will do well with most other coral species if given sufficient room.
Because they are non-photosynthetic, you can place them successfully in dimly lit regions of the tank. In many tanks, that means placing them close to the bottom and towards the corners or in shaded areas.
Sun polyps don’t have any particularly distinct needs, in terms of ideal water parameters. So the standard water parameters are appropriate. You can find out more about those water parameters here.
Sun corals are masters at capturing prey. They will greedily accept Mysis shrimp, brine shrimp, copepods, rotifers as well as meaty foods like pieces of clam, chopped fish or other seafood (scallops, shrimp, etc.).
The key is to have the food chopped up into small enough pieces.
A few quick tips
- Unless you have a tank full of other non-photosynthetic corals, you will want to target-feed your sun corals, which essentially means using a turkey baster or Julian’s thing to direct an underwater puff of food at the open feeding polyps.
- This brings up another important point–many people report that sun corals’ preferred time to eat is after lights out. Over time, you can coax them out earlier, but warned that the sun coral may extend your bedtime (depending on when you have lights out.
- You could feed your sun polyp coral small amounts of food as often as you like, but if you’re looking for a recommendation–start with feeding them 2-3 times a week. Assess whether they are happy and growing with that frequency.
If you have the time and are willing to devote it to feeding your corals, you could increase the frequency up to ~ daily, but this is not a requirement.
You can coax a ‘sleeping’ sun coral into feeding mode by priming the process with an initial small burst of food directed at the closed polyps. You can then wait a few minutes and the feeding polyps should extend. After that, you may feed when ready.
With a little time, patience, and moderate aquarium skills, these beautiful corals are a great addition to a mature tank. The keys are consistent feeding, sufficient calcium levels and giving them enough room to grow.
Your turn—have you kept the sun coral? What has your experience with them been? Please leave a comment below.