Its me again,
Dude I had no idea this tank was that new.
Really I would not put a emperor angel in tank that new. take to a friend or lfs that you trust and have them put it in quarintin tank until you get your tank together. that is a big risk. i am sure it was wild caught. go with the chromis for schooling. i will have enough room in a 300g to try the schooling with the yellow tangs. i will let you know how it goes. also..i would get a hospital tank for that angel right now. he may need to be treated soon! i wish you the best of luck.