The color and appearance of this fish changes drastically from juvenile to adult. The Juvenile Emperor is a dark blue with white concentric circles beginning at its caudal fin and moving forward. The face is also marked with white, as well as its fins. The pattern begins to dissolve into the adult pattern at approximately 4-6 inches. These fish do fairly well in aquariums and prefer lots of rockwork to feel comfortable. The Juvenile Emperor Angel should be kept in a tank of 100 gallons or larger, so it'll have ample room to roam. They will spend most of their day grazing algae that grows on live rock. Angelfish can be territorial towards other species, especially other angels. We have had success when adding multiple species to very large tanks at the same time. Trying to add a new Angel species to a tank that already houses an established Angel usually reslts in aggressive behavior. These fish should be fed a variety of foods including Formula Foods, Mysis Shrimp, ArctiPods, Flakes, Red Fuzzy MacroAlgae, and any food containing sponge.