1st time RTN

[danny zubot]

For the first time in almost 6 years in this hobby I've experienced RTN.
I think I caught it soon though because only half of one colony was lost....hopefully.

I came downstair to feed the fish and noticed the smell, you know, the smell of dead acro. So I looked around in the tank and noticed two colonies showing white skeleton. One, my beloved prostrata acro had tissue slaufing(spelling?) off of it. The other was my pink rimmed cap, but it only had a small section that had whitened. Prior to yesterday the cap was in close proximity to a GSP colony that had killed a very small section of it. I moved the GSP, but didn't trim the effected region of the cap. I wonder if I should have? Anyway, I've prunned the cap down, getting rid of the dead pieces. I'm not worried about that colony as it is very hardy, and needed a good pruning anyway.

I am concerned about the prostrata though. It too is a hardy coral but about half of it was gone by the time I noticed it. I fragged out about 5 pieces and mounted them, and I hope that they survive. It saddens me to see my once 7" across acro deminished to a mere 3" colony.

The only thing I really noticed different about the tank was that the temperature was up to 81.4, from it's usual 80.5 degrees. When I discovered the acro, my smaller tuzedo urchin was in the area of it. It couldn't have caused it to RTN could it? Doubtful, since it scurries around all of my SPS with no ill effects. Other than those two things, I can see a reason why these two colonies would suddenly RTN. Any thoughts?