RTN or other problem?

[scyphozoa]

I have several thick branched acro frags that were doing well the last few months. Lately I have noticed white patches in a few where the tissue looks like it is expelling the zooxanthellae. This has taken place over about a week. I can't see any signs of red bugs (--I've seen red bugs before so I know I can id them). Could this be RTN or is it too slow? Despite what it may be, does anyone have any suggestions of what to do? (In the past i've never had success fragging once RTN is apparent)

 

[Dan Fagan]

RTN will usually set in in a day or so. Could be STN or even FW's

 

[impur]

I just had a slimer STN. I fragged it best i could and dipped the remaining coral in a strong lugols dip to be sure that it was not being eaten by some pest. I didn't find anything. Today is day 3 and there has not been anymore tissue loss. Might be worth a shot.

 

[scyphozoa]

OK, I took one of my patchy frags out of the tank to examine it more closely just in case I missed finding red bugs or flatworms.
Some of the tissue at the base was coming off so I decided to frag it. The good portion I rinsed in fresh salt water & placed back into the tank in another location. I put the dying portion in Lugol's solution for about 5-10 min thinking maybe I'd see problem pests fall off. I did notice lots of very small white objects that fell to the bottom of the container. The best I can describe without magnification is that they are long and narrow like a splinter of wood but also very small, a mm or less (probably in the copepod size range). Is this too small to be AEFWs?