I didn't see your first question, but angelfish will change color in captivity. I had a juv emperor that was a small juv when I bought him and he grew up nice. Once he was about 3 inches or so his lines started to come in horizontal and the fins were turning purple and the face was changing. But the thing is, it takes them a long time to fully change, I'd say a year or two. And its adult colors might not be as bright and beautiful as if it came from the ocean or the emperor won't FULLY change into its adult colors, but most of the time it just takes them a long time to fully change. TJ