The Yellow Tail Damsel is also known as the Yellowtail Demoiselle or the Golden Tail Damsel. It is highly regarded by advanced tank hobbyist as the best damsel overall. Its coloring, incredibly deep blue body and bright yellow tail make any background in your tank pop. They should be kept in a 30 gallon tank or larger with other peaceful fish and multiple hiding places. They will stay away from other fish and coral but can become more aggressive towards fish of its own kind or similar sizes. Feed them mysis shrimp and more meaty foods several times a day to keep them from being territorial.