oh wow cool i have yet to research it because i was unsure of what type it was but I think thats really cool. It was just a random thought anyway Im pretty sure as long as i have food it could care less if i say he or she lol. With that I believe John was right it looks so much like the young Neoglyphidodon melas " Bluefin Damsel" that I say thats what he is! I knew that fish change colors as they get older but my experience is that they get duller looking I am kinda excited to see that he will actually be getting darker, it will be a really cool transformation. Im just guessing this is a older juvenile because i know the old owner had him for 3 years. My concern is so many sites stated how aggressive they get, my guy has been a bit of a dick to my clown but only a few times and the clow has a few great hiding spots to get away to, but i really hope he doesn’t get too mean. I dont like the idea of trading him in, i just have never been that kind of person, thats what the original owner said i should do with both fish and I couldnt they seem happy and i was happy just to have live fish! I also read a lot of different min. tank size does anyone have an opinion on this??