Sun coral losing tissue

[SimonSKL]

I got this beautiful suncoral last September and it has been growing bigger and doing great but about three weeks ago, I noticed a couple of the polyps were losing tissue. It seems to stop now but I wonder if the tissue will return or will it get worse. What do I need to do to keep from getting worse.

Here is a picture of the coral last September.

Here is a picture of the coral about 2 weeks ago when it was not inflated.

Here is a picture of the same coral this morning. Notice the lower left corner where the two polyps with tissue receding.

Any help or suggestion will be appreciated.

 

[DSR]

Looks like it got stung. What is that right next to the area that is dying off?

 

[guitar8222]

It looks like a green slimer.

 

[evsalty]

I was going to say slimmer as well. The acro though is not close enough to sting but if infact a true green slimmer then slime might be a cause. The rest of the polyps look very healthy. How often do you feed it?

 

[SimonSKL]

<a href=showthread.php?s=&postid=15292907#post15292907 target=_blank>Originally posted</a> by DSR
Looks like it got stung. What is that right next to the area that is dying off?

Sorry that I didn't mention the coral used to sit on sand on the bottom of the tank. Because of the tissue lost, I moved it up on the rock. Here is a picture of the coral in May. I had some cyano bloom lately on the sand and I wonder if the cyano caused it. In the picture you can see clearly the affected polyps were healthy at that time.

 

[SimonSKL]

<a href=showthread.php?s=&postid=15293369#post15293369 target=_blank>Originally posted</a> by evsalty
I was going to say slimmer as well. The acro though is not close enough to sting but if infact a true green slimmer then slime might be a cause. The rest of the polyps look very healthy. How often do you feed it?

Right now there is nothing within 1" of the suncoral. I feed it with mysis and brine shrimps about every 2-3 days.