Not dying but receeded. For starters, If you have leather corals, this may be part of the issue. Many leather coral species produce and release toxic chemicals, called terpenes, into the water to protect themselves and to stunt the growth of other species. Many torch owners forget to account for the calcium demand these corals require. If there is insufficient calcium in your aquarium water, these corals will not be able to make their coral skeleton. You should also never lift a torch coral out of the water if you can avoid it. You could tear the polyps, and torn polyps are prone to infection followed by necrosis.
Torches require typical parameters including:
Temp about 78 degrees
Salinity of about 1.025
Ph-t 8.1 to 8.3
Ca level of about 400-440 ppm.
Like most large polyp stony corals, torches benefit from moderate water flow. The polyps will remain retracted and under-inflated if the water current is too fast because the large flowing polyps are prone to rip and tear in high or ultra-high current environments.
Torch corals are photosynthetic coral which have a relationship with symbiotic zooxanthellae (single-cell photosynthetic organisms) that live inside its tissues that converts the light energy into sugar and harvests and feeds the coral. Therefore, it is possible to keep the Torch coral without any feeding at all but bear in mind all corals are animals, and animals are meant to eat. Mysis shrimp is my hoice of food for them.
