Thank you so much everyone for the comments!
It means a lot that you guys think I'm taking good care of him and that he looks healthy.
I was shocked too when I saw how much his color changed since I got him. I almost didn't buy him and went with another one, now I'm so glad I did!
He actually changes color sometimes (at least his head does) Throughout the day it'll go from a darker color to a slightly lighter color. The top of his head also has spots (you can kind of see it in the second picture) I'll have to see if I can get some more pictures of him.
He certainly is mr. personality. He acts more like a dog than a fish and his many different antics can be very entertaining.