Might have an acro STN or just bleaching

Dilan Patel · Jun 23, 2017

Hello I have seen some bleaching and or STN on my new neon green smooth skin acro. It started very slowly. It was doing fine but this week I have noticed it. COuld it be that it is too high in the tank and the lighting is too strong. The tip used to be bright green like the rest of the body now it is kind of like a brownish green. Should I frag the lifing part and then place him lower in the tank. He was dipped as is all the corals I buy. Just do not know what to do. Sorry for the bad photo I will get better photo when lights turn on.

Reefltx · Jun 23, 2017

That is "STN".

Dilan Patel · Jun 23, 2017

Can I ask how you know for future diagnosis also what is the difference between bleaching and STN I know that bleaching is when the coral still has PE but the coral has released its zozanthelle and STN is when the tissue falls off slowly. Right? So is the way to tret this by just fragging the bottom portion and putting it on a anew plug at the bottom of the tank or what. What shall I do I wuld hate to lose this stunning piece.

divewsharks · Jun 23, 2017

Reefltx knows because of what is showing in the picture. STN/RTN typically starts in one part of the coral and then spreads, in your case bottom up. So yes you can cut off the bottom and glue back down -- it need not be on a frag plug, can be directly on the rock or a piece of rock rubble.
As for bleaching, that could be the result of too much light, in this case the coral (at least the portion facing the light) expels zooxanthellae and becomes lightens in color. Could be a little or could be a lot. To prevent this, you would either need to know the details of placement/lights the coral was under and how that compares to your tank. If unknown, then best to take your time to acclimate it to your lights/environment.

hope this helps,