Hiding clown

[outtafocus]

I have a black oscellaris clown who hides n the back corner of my tank. The wierd thing is that he seems to only hide when my metal halide is on. He is out swimming all over when only the pc fixture is on.
Has any one experienced this with their clown before?
He almost seems like he doesnt like the bright light. He isnt a new arrival so it isnt s case of being shocked by the new lighting.
Any thoughts?