Brown Jelly Disease is a bacterial infection and it's no fun at all. Soemtimes it happens with no apparent reason and sometimes it happens after an injury. Either way it's fast and deadly some many soft tissue corals. I lost several different species of "Euphies" in about 3 days due to this.
Good luck and happy reefing.
Oh yeah.. if you google "Brown Jelly Disease" or "Brown Jelly Infection" you can learn a LOT about this and be better prepared for when/if you see it again.
