strange behavior

[pinque]

I have 16 various corals in my 72 gallon reef tank. On one side of the tank, only a leather coral is out , but on the other side , all the corals are out and flourishing...the tank is literally divided down the middle. All the corals were out several days ago, but then suddenly, this happened. Any ideas?

[jenglish]

Are the lights the same on both sides? Based on it being right down the middle that would be my first guess. What sort of corals are affected? could it be a pest that is working it's way across? Walking anemone? Chemical warfare? Just throwing out ideas

[cutietwo]

wow that is interesting. ...hard to say. all the pumps are working properly? recently do a water change?

[REEFIN'ROB]

what kind of lighting do you have? i saw a metal halide with a cracked uv shield once. the corals under the crack got fried. there was a line from the top to the bottom of the tank that had dead corals. everything that wasn't getting cooked looked fine.