I was given this dying Caulastrea “Candy Cane” or “Trumpet” coral and was told it had “brown jelly disease.” Although I had seen plenty of corals with “brown jelly”-like substances, I hadn’t had the mass contagion and mortality that some reefkeepers claimed at the time (although since then, I certainly have). I viewed this coral as a good challenge for rehabilitation. Although, without having a microscope back then, I knew I was taking a huge risk.
Note the damage and “brown jelly” on the four polyps. Image dated 14 March 2012.
First, I assessed the dying Caulastrea coral’s overall health, which was quite obvious. Of course, there was nothing I could do for the polyps on the right, so they were fragged off. The other four polyps looked awful. I dipped them in both Coral Rx and Lugols (separate dips) to check/treat for anything. I also used a pipette to gently blow off all “brown jelly” I could, without damaging the rest of the coral. Essentially, I just followed my standard inspection, dip, and quarantine protocols.
The coral would not take any food for several weeks. Instead, I resorted to just removing the “brown jelly” and maintaining water conditions, which worked in this case.
By 20 May 2012, the four remaining polyps had fully recovered. Once it started eating, the road to recovery was very quick.
I can’t say for sure that this was the typical “Brown Jelly Syndrome (BJS),” but it was still nasty. It left the coral quite ill for some time; it took another seven months to create another polyp. I do recommend extreme caution in cases like this, as BJS can cause massive die-off in the aquariums.
14 March 2012 to 20 May 2012, Caulastrea “Candy Cane” Coral
To see more amazing rehabilitations of previously dying corals, click here!
When I started in the hobby in 2008, there was a legitimate problem with dyed corals and anemones. Sadly, this was not a new problem at that time either. Bleached corals (or even healthy corals) were subjected to dye baths in a dizzying variety of colors, especially in rare shades, such as yellow and blue. Unfortunately, that practice had unsurprisingly deleterious effects on the animals, as the dye interfered with their photosynthesis via zooxanthallae. Fast forward over a decade, and the frequency of dyed corals showing up in local fish stores for sale substantially decreased. So, imagine my shock when a fellow reefkeeper sent me a message about a potentially dyed blue sun coral. The earliest reporting of blue sun corals in the hobby I could find dated back to 2017.
Panic Hits – Artificially Dyed Corals in a Pandemic:
In June 2020, right in the middle of a global pandemic, I was appalled to see reports popping up all over multiple reefkeeping forums and other social media sites claiming that there was a sudden influx of dyed corals. Rehabilitating dyed corals is no picnic; it takes daily feedings, lots of carbon to absorb any free dye, and fast removal of necrotic tissue. Even then, I have never had success with them long-term. Panic started to hit me, as my aquariums were severely neglected thanks to trying to telework and homeschool young children simultaneously. Not only were my tanks ill-prepared, but I couldn’t get the supplies necessary for rehabilitating dying coral. Chlorine bleach and hydrogen peroxide are two of my main staples to keep clean equipment, and they were nonexistent on shelves at the time.
Assessing Blue Sun Coral Health:
Then, on 8 July 2020, a fellow local reefkeeper posted on Facebook that she had just received one of these (on 18 June) and suspected it was dyed and dying. She was concerned that it was affecting her yellow sun coral too, as it seemed to be losing color. So, it was time for me to do some research!
Although I had a lot of questions, my first question was on how to stabilize the coral. Since the owner believed it was dyed, I needed to determine what dyes could have been used so I could figure out how to remove it. Sun corals are often various shades of orange or yellow, so the idea of getting a solid blue coral seemed a bit crazy to me. In other words, I thought that just adding blue dye to a yellow coral would likely result in a greenish coral. However, I’ve used methylene blue extensively, and I know its staining power! It seemed a plausible dye to overcome the yellow.
While researching the various dyes, I found research suggesting that anemones could safely tolerate methylene blue dye, as it did not affect the anemones’ growth or survival. Additionally, the research found that the anemones only retained the methylene blue for approximately six weeks. This gave me hope. Maybe the sun coral was dyed with methylene blue, so it might live if I could feed it adequately (as a non-photosynthetic coral, there is no zooxanthellae interference). I was also prepared with activated carbon to absorb any leaching dye (although this research on using dragonfruit skin was super interesting!)
Bringing the Coral Home:
Only three days later, on 11 July, we met in a mall parking lot, while wearing masks and maintaining social distancing. Even in the hot mid-day sun, the coral was a shocking blue color. I quickly took both the blue and yellow corals home. I followed my standard coral assessment procedure, and several things concerned me.
Determining the Coral’s Condition:
First, I’ve never previously had my hands or equipment get any sort of coloration on them while fragging. Was this the “dye?” I could see blue, yellow, and green colors on this while towel.
Second, the yellow sun coral had a case of “brown jelly disease” starting. This was not good.
Although the tissue appeared dyed, the skeleton of the coral was white as usual. This was not what I expected, especially if the coral was submerged in dye. However, the anemone research referenced above suggests a dye method that may work on just the tissues. At this point, I wasn’t convinced either way on if it was dyed.
Quarantining the Blue Sun Coral:
After initial treatments, I placed the corals into my quarantine tank for observation. I started them on small pellet food, as sometimes that seems easy for corals to digest. Once the coral was regularly eating, I switched it to a varied diet of Roti-Feast, Oyster-Feast, Phyto-Feast, Reef-Roids, and baby mysis shrimp.
Unfortunately, the “brown jelly” spread to my other corals in quarantine, but I was able to keep it from progressing on the yellow sun coral or to the blue sun coral.
About a week after arrival, I was once again convinced that this coral was dyed, as the healing fragmented portion was a dark greenish-yellow. Ah ha!
But this coral decided to just keep me guessing. Wouldn’t the tentacles be blue as well if it was dyed?
Blue Sun Coral Grow-out:
By a month after arrival, I was sure it was natural, as it was just becoming more blue with bright yellowish green polyps. How was that possible?! Methylene blue should’ve mostly dissipated by that point. It had to be natural, right??
Oh but wait… This coral just wants to keep us on the edge of our seats! After four months in my tank, the shadowed areas were turning yellowish green! But, notice the baby polyp – it’s blue! My head was starting to hurt. (And yes, unfortunately I was not feeding the coral as much as necessary, so it was receding. My tanks were quite neglected during COVID-19, as you’ll see by the algae and aiptasia.)
In reviewing the 2017 post photo, the shaded regions display similar coloration.
Spawning of the Blue Sun Coral!
On 12 December 2020, five months after getting the coral, I woke up to find this blue sun coral spawning! And, the planulae were orange (not blue) – suggesting the coloration was natural (and reproduction hopefully not affected).
One of the planulae immediately settled onto the glass, where I watched it eagerly (until it disappeared about three days later).
Blue Sun Coral Spawning
Here are some of the planulae. Unfortunately, none of them survived, or maybe they weren’t even fertilized in the first place.
According to username, “Tennyson,” on Nano-Reef, the dark orange/ brown ones are “duds” while the more yellowish planulae are viable (assuming this is consistent across all sun coral colorations).
(For more reading on sun coral reproduction, please see the references below.)
Although the tank wasn’t exactly clean, both sun corals were appreciating the high nutrient levels!
Final Thoughts:
Although I took this photo under actinic lighting, the blue of the sun coral is very similar to the blue of the Oregon Blue Tort Acropora coral. This amazes me as one is photosynthetic while the other is not. In advertising the Oregon Blue Tort, there are plenty of websites that describe the blue as “so vivid it makes you wonder whether it was injected with an artificial blue pigment,” “often considered the bluest Acropora coral you can buy,” “one of the bluest of the blues,” and “so blue it almost looks fake.” I can see why this blue sun coral was also believed to be dyed!
Conclusion:
Over 13 months later, here it is (under actinics again, so the yellowish green polyps are hard to capture on the camera). I lost four polyps, and a few polyps shrank but are now re-growing. The coloration hasn’t changed a bit. The tissue is brilliant blue, the tentacles are yellowish-green, the oral cavity is yellowish-green, and the center of the polyp is blue. Shaded areas turn yellowish-green, but they regain the brilliant blue color once exposed to light again. This makes me believe it’s a structural blue versus a pigment.
Although I lost four polyps, this gives me an opportunity to clean the skeleton to help identify the coral (to be included at a future point). I am convinced that this coral is not dyed, but I have no explanation for its coloration, especially as blue is rare in nature.
So, let’s celebrate this amazing coral with a happy ending. It was fate that on 25 July 2021, the Washington D.C. Area Marine Aquarist Society (WAMAS) hosted a virtual meeting with guest speaker, Matt Wandell, from the Monterey Bay Aquarium. His topic was on “Use and Care of NPS Corals.” Of course, I had to chat with him about this unusual beauty. I am happy to report that we have made arrangements for at least half of the coral to go on display at the Monterey Bay Aquarium in the fall of 2021 (once the weather cools down).
Mizrahi, D., Navarrete, S. A., and Flores, A. A. V., “Groups travel further: pelagic metamorphosis and polyp clustering allow higher dispersal potential in sun coral propagules”, Coral Reefs, vol. 33, no. 2, pp. 443–448, 2014. https://core.ac.uk/download/pdf/37522324.pdf
Wells, CD, Sebens, KP, “Individual marking of soft-bodied subtidal invertebrates in situ – A novel staining technique applied to the giant plumose anemone Metridium farcimen (Tilesius, 1809),” PLOS ONE 12(11): e0188263, 21 November 2017. https://doi.org/10.1371/journal.pone.0188263
Even on a smaller scale than global reef decline, the ability to assess coral health is essential. I am often asked how I know where to even start to rescue corals. In my opinion, determining how healthy the coral is, or what the problem might be, is usually the first step. This is an introduction on assessing coral health to determine what might be causing the coral stress.
Assessing Coral Health for Stung Corals:
Corals stung by another coral are probably the most easy to save. These corals are healthy overall, but a portion of them is damaged. As long the coral avoids infection and no further damage occurs, then healing is rather quick. When a coral “stings” another coral, the stung coral is sometimes actually “digested.” When corals have to compete for territory, they expel their digestive organs, called mesenterial filaments, and use them to digest a nearby coral. This typically results in one area of severe damage and no damage elsewhere. A coral stung this coral shown, but the remaining tissue was very healthy. You can read more about the Trachyphyllia’s recovery here.
A lack of proper husbandry is typically a slow process. It can result in the tissue between polyps receding first. As shown here, portions of recent die-off right are beside healthy tissue and coralline-encrusted skeleton. With these corals, good water parameters are essential. Removal of invasive algae is also critical. These corals typically do not need much additional care. You can read more about this Lobophyllia’s recovery here.
When a coral is improperly fragmented, various outcomes are possible depending on damage. Sometimes the tissue rips apart improperly, or the skeleton is crushed underneath intact tissue. As long as there is about half the polyp left, the coral typically survives with the natural healing process. This Euphyllia coral unfortunately became infected and died.
Attempting to rescue an infected coral is risky, as it may infect other corals. This type of rescue requires a proper quarantine tank and medications on hand. Typically, once the pests and any eggs are removed, the coral will heal quickly on its own. Here, this infected Acropora has both Acropora-eating flatworms and red bugs (Tegastes acroporanus). With proper treatments to remove both pests, this coral made a full recovery.
Attempting to rescue infected corals can be dangerous, complex, and expensive. Any attempts require a dedicated hospital tank, proper supplies (including a microscope), and extensive knowledge in coral diseases and treatments. Furthermore, keeping a low expectation for coral survival is key. These infections vary by cause (e.g., bacterial, viral, fungal, ciliate, etc.), so the owner must tailor treatment to the cause. Determining the cause can be nearly impossible without the proper equipment. Any attempts also require the utmost caution, as some infections are transferable to humans. This coral shown had “brown jelly disease.”
Coral bleaching also has a variety of causes, and knowledge of the cause can help determine possible solutions. Assessing a bleached coral’s health can be challenging as high light, chronic low light, high temperature, low temperature (rare cases), lack of oxygenation, and some infections can cause bleaching. Since a bleached coral is lacking its typical zooxanthallae population (the symbiotic algae that lives inside the coral’s tissues and produces food for the coral), it will need regular feedings. Unfortunately, in my experience, sometimes these corals never thrive again, even with coloration return.
The photo below shows several corals that were poisoned with household bleach. An angry customer poured it into a local fish store’s tanks, which killed all the livestock. I attempted to save everything that still had tissue, but even these corals eventually died.
Corals bleached with…bleach. These were the victims of an attack on a local fish store.
Although starvation is more commonly seen in non-photosynthetic corals (NPS), it is still possible in photosynthetic corals as well. This is more likely to occur in in ultra-low nutrient systems, also known as ULNS. Here, a Dendrophyllia coral is starving, shown by the algae-encrusted skeleton. Regular feedings are essential in these cases.
Poisoned corals usually have retracted tissue with areas of white skeleton showing. Tissue colors are usually brown or white, depending on the toxin. Any other typical colors (e.g., blues, reds, greens) are muted. This coral was poisoned by either the flatworm treatment a LFS used, or by the flatworm toxins themselves. You can read more about this coral’s amazing recovery here.
As shown, coral health has a multitude of causes, and only a few examples were shown here. If you would like to continue learning about coral pathology, a more technical source is available on NOAA.
