I am a newbie to FH's I thought it was a nice one but I noticed sometimes the red on the face fades kinda. Well it was faded when I got it home and then brightened up then faded again when I moved it to another tank. Is this normal ? none the rest of it fades that i have noticed just the red on the face. when it fades the head looks more like a bluish green with a red tint, after a couple of hours it back to red again.