Blue Ring Angelfish
The Blue Ring or Blue-Ringed Angelfish is also known as the Annularis Angelfish and the Blue King Angelfish. It is a good candidate
for intermediate marine aquarists. The Blue Ring originates in the Indian and Western Pacific Oceans from Sri Lank to the Philippines.
It can be found lurking among caves and hidden areas in coral reefs from 5m to 30m in depth.
The pomachanthid family is named after the Latin words "pom" (cover) and "acanthus" (thorn), which
refers to its large spine on the lower, rear margin of its gill cover. This spine distinguishes
angelfish from butterflyfish. The spine gets easily tangled in nets and injures intruding fish.
Many pomachanthidae share a common characteristic that the young are a totally different color
pattern than the adults. In fact the young of differing species can look more related to each
other than to their parents. The Blue Ring Angelfish is typical of this pattern.
The juveniles stay nearer to the surface than the adults. Juveniles are dark blue to almost
black, with white curved bars on the body. The juveniles are often confused with the Goldtailed
Angelfish, Pomacnathus chrysurus. The latter is distinguished by its yellow caudal fin.
When young, all Blue Rings are females. The adult Blue Rings become dark orange to brown with
distinctive blue curves and a blue ring just above and behind gill cover. There are also two
blue stripes on the face - one through the eye and one below this. The caudal fin is white
with a yellow fringe. In the wild, adults can grow to 45 cm.
In the wild, the
Blue Ring Angelfish subsists on algae, sponges, zooplankton, coral polyps, shrimp and shellfish.
As adult angelfish develop a dependence on sponges, try to obtain a younger specimen which will
eat algae and meaty foods, such as mysis and brine shrimp. Julian Sprungs Sea Veggies, Ocean
Nutrition Seaweed Selects and standard spirulina flakes are all excellent choices. A high
quality sponge based flake food, such as Angel Formula by Ocean Nutrition, should also be used.
The diet can be supplemented with small amounts of chopped fresh and frozen crustaceans,
shellfish and squid. The Blue Ring should be fed several times per day, but care should be
taken to ensure all food is eaten immediately so that water quality is not impaired. Due to
their interest in eating crustaceans, clams and soft corals, they are not a good choice for a reef tank.
The Blue Ringed Angelfish is very territorial, so only one of the species and preferably
on one Blue Ring should be kept in an aquarium. A tank size of at least 70 gallons is
recommended. Also, the Blue Ring should not be kept with other angelfish as they will
fight aggressively. An angelfish should be introduced last in a community tank. Float
the angelfish in a transparent tank to get an indication of compatibility.
Possible tank mates include Dwarf Angels, Wrasses, Damsel Fish, Clown Fish, Butterfly Fish
and Tangs. Tangs are riskier tank mates though. The tank should be well lit and have strong
waterflow and bubbles to play in. It should have hiding places and live rock for feeding. If
your angelfish doesn't have adequate room, it will be more
In the wild, Blue Ring males defend several females in a very small area. Blue Ring Males and
females are not distinguishable from each other. They are egg-scatterers and usually breed at
dusk. In the wild, the larvae drift for a month before developing into juventiles. In captivity,
the larvae rarely survive.
||22 - 26 C; 72 - 79 F
||8.1 - 8.4
||8 - 12
||1.020 - 1.025
||30 cm; 12 inches
Does well in a Fish Only tank. They should not be kept with other Angels and only one should be kept per tank. Suitable tank mates include Butterflies, Tangs and Wrasses.