Looks like Hydnophora to me.
It's an SPS and depending on your lighting, will not survive on the sand. they require a decent amount of light.
Needs higher placement and more flow.
Looks as if the lower sections were bleasched and they'll get grown over eventually. It has potential.
i think it is a hydnophora. i have one like it and it also has the white at the bottom but i hope it will grow over it. it has been that way since i bought it maybe two months ago.
If you thought that was bad I bought about a year ago a hydnophora from the damaged tank at my LFS for 5$. It was a football sized colony with only 2 1" branches that had any tissue remaining. I cut these branches off and glued them down, it took months to regain good growth but became a nice frag. Hydnophora is a very hardy SPS and yours should make a full recovery, is it bleached or has the tissue reccesed? Be very carefull or RTN could still set it.
I was also suggested by someone there is a STN that reqiures fragging the SPS out to stop it. Otherwise the tissue will continue to recede untill the coral eventually dies HTH
