RTN help

[Beautiful_chaos]

I just recently added a few new frags to one of our tanks. It's my first time trying SPS corals. I've added three. One is doing great, one is okay (puffer is snacking on him) and this one I saw yesterday started flaking it color off. Within an hour and a half it was to this point (see photo).
I removed it from the tank, set it out for an hour or so, then I placed it back in water. It's no long flaking.

Is RTN what it sounds like to those who have had experience with it?

How long before I can put it back in the main aquarium without risking the chance of infecting the other corals?
Or is it wise to return it to the tank period?

I know this is long winded, but this is my first actual saltwater aquarium (I grew up around aquariums) so I'm try to learn all I can and take every pro caution.

 

[Beautiful_chaos]

Another photo

 

[EuroGTI]

Unfortunately that piece will prob not make it. If the tissue necrosis slows down, you can frag it and try to save it. Stn and rtn are not really infectious. Just because one coral has necrosis, does not mean the rest will. In some cases you can have a whole tank rtn or Stn, but that obviously because something went wrong.

 

[PaleHorse]

http://www.reefcentral.com/forums/showthread.php?t=2430841

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