Is this STN? Plus ID needed for another SPS frag.

[ug.mac]

Hi all

I'm having this issue for about a week now, maybe a little longer. Basically as you can see in the picture, middle of the coral body is slowly turning white, along with lower edge. I think it looks like STN (from what I've been reading, never experienced one) but not sure (I'm hoping it's not a kind of contagious disease). I don't have this issue with any other corals in my tank.

I got this frag last year and didn't grow much. Just to compare, the frags on both sides were bought same time and same size from same tank.

Here is the picture:

Plus, can anyone ID this SPS frag please?

My tank parameters:

Temp: 25.5 ± 0.1 c˚ controlled by RKL
Salinity: 35 ppt
PH: 7.8
NO3: 0
PO4: 0.02
Cal: 440~450 ppm
Alk: 9 dKH
Mag: 1300 ppm
Potassium: 400 ppm

I'm dosing:
Vodka
ESV Iodide
BW Postassion
BW Magnession
BW Kalk+2 in ATO (thin ratio @ 0.75 grams to 1 gallon, will increase next mix)
Aquavitro Fuel
KZ ZeoBak
Fluval Active Carbon in TLF 150


Thanks in advance.

ug.

 

[drw94]

Regardless what is happening to it, I would frag the bad parts off and throw them away. I honestly believe that when a coral looses tissue and dies it releases toxins that may or may not affect other corals. I know I am the minority on this, but it is just my opinion. The other corals look great and have no ID on the other.

 

[ug.mac]

Thank you drw94. I'm planning on using superglue first tomorrow to see how that works for me, if not then I will cut it off.