I have 3 3" Keyholes they do tend to throw colors off on the mood swings possibly is what your seeing..
That is kind of what I am thinking. I think he gets excited and gets the red. At that time the rest of the color is the nice light tan with the defined spots. Much different than the "I just woke up" mottled browns. And if I remember correctly, the rest of his fins might be well displayed at that time as well.