I have long known that Hydnophora while very beautiful and a prolific grower in poor conditions was dangerous I continued to keep this devil of a coral. I have two pieces that I originally got from Fisher 12 about a year ago that have tripled in size and I had assumed had attached to the rock where it resided. My urchin let me know otherwise the other day when it plowed through them knocking them over. One tumbled down over my prize cup coral the size of a dinner plate and on to my Duncans. The duncan polyps quickly took cover inside their skeleton but the tissue of a cup coral has no such defense. I do not believe that the Hynophora came into contact for very long but the result is very very evident. I have brushed the tissue clean and will watch it for the next couple of days as my experience with cup corals has proven that it is one of the few corals that will expend energy repopulating damaged skeleton with tissue, as it has done in the past. If not I will have to cut out the necrosesd area. Hynophora is a great first sps coral and does will in crappy water conditions but it is a killer so be careful. I included a picture of what a full colony looks like.
Hope it comes back Chris. They are very agressive corals and some believe they can put out toxins even into the water and well not keep them in a tank with touchy acros, don't know how real that is. They can for no apparent reason also start to turn to brown jelly. I had a flor. green one for 6 mos. and got a rare blue one from NSA which was doing beautifally and all of a sudden started to show skeleton spots and brown jelly around the areas. It got worse and I tried several logols dips, which did nothing to slow it down. Then it went to the green one ane within a few weeks both were gone and it affected none of the other corals, just the hydros. Never seen this happen before. Scott at NSA said another fellow lost one at about the same time which he had for quite awhile and was 24" across and for no apparent reason did the same thing. I figured mine happened because I added the blue one but the other guy didn't add anything new, so who knows. I have since learnt that they are prone to doing this and no one knows why.
Update - It has only been a couple of days and I have already notices specks of tissue starting to grow on the bare white exposed skeleton. The coral does not regrow tissue by moving a healthy edge back over the tissue but seems to do it by scattering cells that grow tissue over the damaged are like plugging a yard to grow grass. In the end all the little specks grow out and fill in the dead space. I will post a picture when they are more evident. I waited several days to post a reply because I wanted to be sure about what I was seeing and not algae growing on the dead skeleton.
Guess it works kinda like hair plugs. Should be interesting to see how it grows. Anytime you get ready to FRAG that thing be sure and give me a shout.
My yellow polyps killed half of a frag of hydnophora in less than three hours. I guess my yellow polps have some strong ju-ju. Now the hydno is sitting in the frag tank but it has not shown any sign of growth,hope your cup coral heals up, be a shame to lose it.
So this is the coral two months out, as you can see it has completely healed over and some of the polyp in the area that still had tissue inside grew back. I am very pleased at this system and its ability to be stable for my corals to heal after such a tramatic attack from a neighbor. The coral is oriented a little different post aquascaping so the burned white skeleton that has healed is at the top of the coral now.
