Xenia losing it's top?!?

[barjam]

Has anyone else ever had their xenia (all of it in the tank) lose it's tops? That happened to me over the weekend and I assumed that it was all going to die. It still looks like crap but it looks much better than it did and is improving every day.

I am not sure what even caused it. It started when I was checking out my tank and noticed my YT was kind of acting a tad funny... I panicked and decided to do a water change (one was on schedule anyhow)... 10% as I usually do. After that I was watching the tank and figured out what Tang's problem was... he was constipated. Once that worked itself out he was perfectly fine. Then the xenia started it's downward spiral. The tops started shriveling, then started falling off. No other coral in the tank was effected immediately. The next day the xenia was starting to shed it's skin a bit and my toadstool & colt were closed for part of the day.

Sort of weird I thought.

Params:

PH 8.4
DKH 9
Ca 430
Nitrates 0-10