I have a 40 gallon reef only tank, with 175 watt MH
lights, one piece of Povona (leaf coral) frag
, two Tridacna clams, several mushrooms, xenia (spread out), small star coral, one candy cane coral and a branching hammer coral (about 6 branches).
My question is that over the last 6-8 months, the branches of the hammer coral appear to be dissolving. All pH, Nitrates, Nitrites, Calcium, Iodine, Salinity, Temp,… appear to be normal (maintain most through additives). The clams (I have had them for over two years) and the Povona (1.5 years) are growing (I can see new growth) and doing well. The Hammer has lost some of it's color, but still appears to be doing well. It is even sprouting new “tentacles”.
I am concerned because I think that one of the branches will be falling off within the next several months.
I thought that pH might be a problem, but after testing regularly, it appears to remain constant. Any thoughts, ideas or help would be greatly appreciated?