Pygoplites diacanthus (Regal Angelfish) Max size: Usually does not exceed 8-9 inches in captivity. Temperament: For the most part, peaceful.When first introduced it will most likely be extremely passive and shy but once it get used to the environment it will be out all day grazing on rocks and substrate. Mine is no longer scared of me, when I approach the tank it will rise in the water column and wait for food. Reef compatibility: The Regal Angelfish is known as one of the safer Angelfish in reefs. I have mine with SPS, LPS, and some Zoas, it has yet to touch anything. If kept in a fish only system it MUST have live rock to graze on. Difficulty: It is known as one of the tougher fish to keep in our hobby, most will never accept food in captivity. The key is getting a healthy specimen from the start. Buy from a reputable dealer that knows how to get finicky fish eating. Also, avoid specimens caught from Pacific waters, they are known as much tougher to acclimate to captivity. Try to get a "Yellow Bellied" specimen caught from either the Red Sea or the Indian Ocean. Feeding: As mentioned before Regal Angelfish are very finicky. The first week I had mine it would sample some foods but it would always spit them out. I decided to try fresh clams from the grocery store, and my Regal devoured them. It was almost a month before mine FINALLY decided to eat frozen Mysis and Rod's frozen food. Mine now eats anything, including pellets. If you have a Regal that refuses food, I highly reccomend trying fresh clams. Notes: Just like all Angelfish, the Regal is very susceptible to the Trematode parasite known as "flukes". It is recommended to quarantine and treat with Prazi Pro medication before releasing to the Display Tank.