Open Brain Losing Flesh

[migston]

I've got a green trach that appeared healthy when I bought it around two weeks ago. However, I've been noticing a small piece of exposed skeleton that's been getting bigger and bigger. There are now something like 6 spines showing.
Tank stats:
ammonia - 0
nitrite- 0
nitrate - <10
ph 8.2
SG 1.025
temp 79-81
calcium 405
alkalinty - 3.0 meq/L
4x54 watt T5 lights
Brain was placed on the substrate initially. I then moved it up closer to the lights and it didn't help. Last night I put it in a specimen container to isolate it in case it was being nipped. No improvement and I was worried about the lack of flow. So I put it back on the sand and chopped up a plastic water bottle to cover it.
In addition to the receding flesh, it looks like it's got this semi clear white mucus coming off of it.
Is this brain beyond help? I thought this was supposed to be a hardy coral? So far, my two hammers and my long tentacle plate are doing great and they're supposed to be hard to keep.

 

[stuckinfla]

Might be low in Cal, Alk & lights.

 

[dburr]

It may have a bacterial infection. Have you tried a Lugouls dip? Sometimes it works.

 

[migston]

I had the same thought about the lugols. I went and bought some today but since I had a ton of errands to do, I didn't get home until 1am. When I pulled the brain out for the dip, all the flesh fell off. I'm now stuck with a very expensive piece of base rock.
Do you guys suggest I lugol dip all my future new corals before introduction to the tank? I was under the impression that it was done on SPS only to prevent parasites of some sort. Does it also help cure bacterial infections? If so, then it will become common practice for me from here on out.