How long did you have it?
Was it like that when you purchased?
It could be lots of reasons.
First if was doing well at
LFS, did they happen to packed the coral out of water?
Whenever purchasing corals, ask them to pack them under water to avoid any possible injuries/damages when taken out of water. You should do the same as you introduced corals to your tank unless corals are well closed/contracted. Weight of water in body can pull tissue/skin off the skeleton which can/will cause such meltdown.
If at any time you notice such tissue/skin deteriorations, should observe closely and learn how to treat if necessary.
Most of corals are wild specimen otherwise stated fragged in captivity. I would do whatever I can to keep them alive as long as possible in my care. Have performed very unorthodox methods to save/cure when such mishap takes place, no matter how small the portion (popyps) maybe.
You can do little research online for more orthodox methods of diagnosing/treating them which will help you notice such mishaps in early stage. That in turn will give them a better fighting chance.
Secondly, I have experienced when salt crust from tank rim, glass canopy, lighting have fallen on top of coals, meltdown did occur. So becareful when performng regular maintenance on the tank.
Calcium? Possibly but in doubt! I believe it wont hurt to check though.
Water Parameters? As long as
pH is ok, should not be a problem. Coral do not have respiratory system like vertebrates, so
NH3/
NO2/
NO3 is not that detrimental as long as w/i reason. Corals have
zooxanthellae, symbiotic algae, thus requiring better lighting, and also can utilize some NO3, PO4, etc.
Dont mention it, just glad to be able to assist.. hope rest of hammer is not affected.
Cerianthus
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