Normal or not green plate coral

[stimpy4242]

First plate coral, is this normal?
http://picasaweb.google.com/philipdepalo/TankParty02
Is its mouth open that much for feeding? I have only seen it closed...
Thee three pictures two are closed one is open...is it normal?

 

[perfectdark]

Yes mine does it often, I've had it for over 10 months.