Dead bellus

[losthere]

I noticed my bellus acting very reclusive last night and today it is dead. It was eating fine yesterday, and I did not notice any signs of illness, just hiding in the rocks and only coming out to eat.
I also have a flame wrasse and a sunburst anthias and they seem fine, and are eating great.
Anybody have any ideas of what happened? Should I be concerned about the other fish?