fiji foxface

First time owning a foxface, I know they can change color. I went down to see my foxface tonight and notice his color was bacially different. His black was now almost white but still had a lot of blacks is this normal behavior at night?

Anyone ever had a tang act like a total scaredy cat and hide all of the time? We've had three tangs for about a year in our 125 gallon reef tank: a yellow, cole, and blue hippo. They are all around the same size and always gotten along. About a month ago we added a Fiji foxface to help with a...