|Latin name||Pomacanthus semicirculatus - (Cuvier, 1831)|
|Common name||Semicircle angelfish|
|Family||Pomacanthidae - Pomacanthus|
|Origin||East Indian Ocean, West Indian Ocean, Australia, Japan, The Red Sea, Indonesia, East Pacific, Central/West Pacific|
|Max length||40.0 cm (15.7")|
As aquarium fish
This species can be extremely aggressive towards other fish.
Be careful when keeping these fish together with peaceful or docile species. Regular feeding, plenty of hiding places and a lot of space can alleviate aggressive behavior to some degree.
High water quality
This species demands a high water quality.
Amongst other things it means, that water must be properly oxygenated.
Can nibble at clams
This species sometimes nibbles at clams including Tridacna species.
This fish requires feeding several times a day, especially when newly added.
When the fish can find its natural food in the aquarium it requires less frequent feeding.
Well established aquarium with algae
These fish should be kept in a well run aquarium where they can "graze" algae from rocks and stones.
If there are insufficient algae on the rocks, it is important to feed more frequently and supplement with algae rich food e.g. Spirulina.
Acclimitises best as a juvenile
This species will better acclimatize to the aquarium`s condition if introduced, when young.
Very small individuals can be very delicate.
Requires a varied diet
This species must be fed with an appropriately varied diet.
Requires plenty of space for swimming.
This species revels in swimming and requires an aquarium with ample space.
This species can change gender from female to male.
When a male is needed, a female changes sex and takes on the role.
Bred in captivity
This species can be bred in captivity, one can therefore consider asking your local fish store for a captive bred specimen.
This species can eat large amounts of algae (relative to their size) from rocks, like green hair algae and filamentous algae.
As it doesn’t eat every algae type, in case of a specific algae plague, find out more precise information.
This species can be very shy when first introduced into a new aquarium.
More aggressive fish can be introduced after this species has acclimatized.
This species needs good hiding places, for example, between live rocks.
Can coexist as a pair
They can live as a pair provided they are introduced simultaneously.
This species can make a grunting sound when it feels threatened for example.
Refuses to eat at first
This species can refuse to eat when newly introduced.
Normally however, they begin to eat within about a week, but it's advantageous if they can find their own food in the aquarium.
Tips for keeping Angelfish
It is possible to keep various different sizes of Angelfish in the same aquarium, but it means that one must choose species with care and that the conditions in the tank are optimum.
Here are some suggestions to increase the chances of success:
Choice of species
It is important not to choose species that are too similar, the greater the variance, the larger the chance of success. It is also advantageous to choose fish of different sizes. Two young Angelfish of the same same size and pattern for example are a bad idea. One should of course avoid the most aggressive species.
Order of introduction
It is a good idea to make a wishlist and choosing the order so, that the least aggressive are introduced first. When adding similar sized Ange fish it works best if they are introduced simultaneously.
There should be enough space in the aquarium, but it is difficult to give specific advice. Of course there are exceptions to the table below as to just how big a tank should be in order to stand a good chance of success. Space itself is not enough, there should also be sufficient hiding places so the fish do not have to fight over these.
100 gal (400 liters): Several small Angelfish (<15cm) can live together.
240 gal (900 liters): Several medium Angelfish (< 20cm) can live together.
400 gal (1500 liters): Several large Angelfish (<25cm) can live together.
Food and water quality
It is always helpful to give the fish a varied diet, so they can withstand the occasional stress situation when for example new fish are introduced. Water quality must also be very high, so that the fish do not get stressed for that reason either.
Corals suitable for an aquarium with Angelfish
It can be a challenge to keep corals together with Angelfish, since the latter eat most soft corals and LPS. Especially Zoathus are swiftly eaten by the larger species.
It is however possible to build up a mixed coral aquarium with Angelfish. If some of the following corals are choosen there is a good chance the Angelfish will leave them alone; Hammer corals, Bubble corals, Star polyps, Disc anemones and others.
Most of the SPS corals can be kept with Angelfish.
When young these fish are black, with white and blue stripes.
Genus description (Pomacanthus)
The Pomacanthus genus of Angelfish, is extremely impressive with their beauty of colours and patterns. They live mostly on most sponges, but also soft corals, tunicates and macroalgae found naturally.
There is typically rather a large difference in the appearance between juvenile and adult.
When properly fed, these fish can grow fast and become very large. In captivity, it can take well over a week for these fish to start feeding. This, because they are not used to catching their own food in the aquarium. It is best to feed them little and often, 4/5 times daily.
As the feeding indications suggest, these fish are not reef safe, but if one chooses the corals with care, it is possible to keep them together in a aquarium.
One may obtain a species specific preparation containing sponges to meet nutritional needs of some species. Thier diet should include algae based foods, i.e. nori seaweed, spirulina, or similar.
Pomacanthus species can be very aggressive, but not to the same degree as the Holacanthus. Thus in a tank with shyer species it is best to add a Pomacanthus last.
They must also not be kept together with Lionfish, Seahorses, Scorpionfish or similar, as they might be nibbled.
Family description (Pomacanthidae)
Angelfish (Pomacanthidae) are known as some of the most colourful and impressive fish on the reef.
Many species are not reef safe, as they especially target the soft corals and LPS. But by choosing your corals carefully, or by getting specific species of Angelfish, they can be kept in coral aquariums.
There are Angelfish suitable for most aquarium sizes, from Dwarf Angelfish which are well suited to smaller aquaria, to the larger of the species which can be impressively displayed in a larger aquarium.
The demands of the individual species can vary widely. Some are food specialists and require therefore special food, while for others can be difficult to acclimatize, as they live in deep water in the wild. It is recommended that one has a reasonably good knowledge of the different types of food and of treatments of illnesses, if one wishes to keep the larger species.
|Distribution||Indo-West Pacific: Red Sea and East Africa to Samoa, north to southern Japan, south to Western Australia and New South Wales, including Lord Howe Island (Ref. 1602).|
|English common names||Semicircle angelfish, Semicircle anglefish|
|Danish common names||Koran-kejserfisk|
|German common names||Koran-Kaiserfisch|
|French common names||Chirurgien tabac, Poisson-ange à demi-cercles, Poisson ange bleu|
References and further reading
Niels K. 2014. Private conversation - saltvandsforum.dk - (Danish)
Scott W. Michael. 2004. Angelfishes and Butterflyfishes (Reef Fishes Series Book 3) - TFH Publications / Microcosm Ltd. - (English)
Bob Fenner. Marine Angelfishes, Family Pomacanthidae - Wet Web Media - (English)
Bob Fenner. The Best Angelfishes For Marine Aquarium Use - Wet Web Media - (English)
Bob Fenner. The Ultimate Angelfish Aquarium; An amazing and challenging collection of marine angelfishes - Wet Web Media - (English)
Collection of links to additional information - Wet Web Media - (English)
Reef Central. 2009. Keeping more than one emperor angelfish together - (English)
Froese, R. and D. Pauly. Editors. 2014. FishBase. World Wide Web electronic publication. www.fishbase.org, version (08/2014).
|hermaphroditic, aggressive territorial, algae eater, herbivore, docile shy, pair couple, eats tridacna, angel, tag_kejser|