Long tentacle plate coral problem

[apexifd]

I have a long tentacle plate coral that I got a few weeks back... and just about last week, I have notice some flesh damage. It was about 1/4" of skeleton showing, and it stay like that for few days, and today, I found it to loose another 1/4" of flesh.

so, is there anyway I can help the coral to heal itself?? target feed certain food to promote healing?? hospital tank(have a 4X24w T5 fixture and a 40g breed not in use @ the moment).

thanks