Hey Regina. I think I do have some literature about color morphs in angels and Tangs. I will try and dig it out. As far as the color morphs changing when the fish are kept in captivity. Many believe it is a dietary issue. The color morph is caused by them eating very specific food items. In other cases, especially in Tangs. The color morph is caused by a harmless fungus they acquire when they are young in life. In this case, such as koi tangs, the fish usually keep these colors. T