|Latin name||Chromis atripectoralis - Welander & Schultz, 1951|
|Local name||Black-axil chromis|
|Family||Pomacentridae - Chromis|
|Origin||East Indian Ocean, West Indian Ocean, Australia, Indonesia, East Pacific, Central/West Pacific|
|Max length||12 cm (4,7")|
|Minimum volume||300 cm (79 gal)|
|Suitable for aquarium||Suitable for most aquarium|
|Reef safe||Always reef safe|
Zooplankton (Cyclops, pods...)
Small crustaceans (Krill, mysis, artemia...)
This species is very sensitive during transportation and acclimatizing into the aquarium.
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.
This species is happiest as a pair or in a shoal. A shoal should consist of 1 male to 5 or more females.
They can be aggressive towards each other, so in a small shoal there can be aggression towards one specimen, but this can disappear over time.
This species can be bred in captivity, one can therefore consider asking your local fish store for a captive bred specimen.
This species likes to hide in and amongst the branches of corals, e.g. Acropora coral and
will also do well if they can find other hiding places.
These fish swim in shoals at the fish store or when newly introduced into the tank.
Some aquarists report that after a while in the aquarium, their fish stop this behavior and can then become aggressive towards each other.
When fully grown, these fish develop a black spot by the pectoral fin, the only way to distinguish them from Chromis viridis.
Chromis are often seen in large shoals in the fish store, but note that they might stop shoaling when sexually mature. When they are mature, they will become more aggressive towards each other. If a larger shoal can be kept, the aggression can then be directed towards several individuals, thus increasing the chances of success.
But in comparison to the other species in this family, the chromis are reasonably peaceful.
Clown-/Damselfish (Pomacentridae) can be divided into three groups as described below.
Clown-/Anemonefish (Amphiprioninae) are characterised in that they spend most of their time in an anemone. They can be kept outside of one and sometimes will find another coral to hide in. This can be Hammercoral, Xenia or similar. Clownfish exhibit fascinating social behaviour, especially when carrying eggs. This is even more interesting when kept with an anemone or a substitute.
They go normally in pairs and most are easy to keep in aquaria. Clownfish can easily be kept in small tanks, as they do not swim around a lot.
It is important to have a male and female or two males to one female, as two females do not tolerate each other. When one acquires two fish of very different size or two small individuals, it is likely they will become a pair.
When setting up a reef aquarium, Clownfish are the obvious choice. They can be aggressive towards other kinds of fish, but mainly when these get too close to their hiding place. They do tend to get more aggressive when they have an anemone or when carrying eggs.
Most of Clownfish are of the Amphiprion genus, but there is a single species in the Premnas genus.
Chromis (Chrominae) encompass the genera, Acanthochromis, Altrichthys, Chromis, Azurina and Dascyllus, but when talking about Chromis it is normally understood to mean the fish of the Chromis genus specifically.
Fish in the Chromis genus are not as hardy as the Clown or Damselfish, but are very attractive with their shiny blue and green colour nuances. Overall the fish in this group are less aggressive than many others in this family and are often seen in shoals. They do become more aggressive when pairing or laying eggs.
Fish in this group live mainly on zooplankton and must be fed frequently, if possible several times a day.
Some in this group are often seen hiding in stony corals e.g. Acropora, but some species may look for shelter in anemones.
Damselfish (Pomacentrinae and Lepidozyginae) are typically hardy, very attractive, but very territorial. Some species are very coulorful when young, but become dull over time.
They live typically of a mixture of zooplankton and algae, some live more on algae and some on zooplankton. Some Damselfish even cultivate their preferred algae in a small "garden", so they have their own foodsource. This does explain their aggression towards other fish and invertebrates, which want to eat their algae.
Because of their territorial behaviour it is best to keep only one Damselfish per aquarium, unless it is a very large tank. One should consider not acquiring Damselfish, if at a later stage very peaceful or docile fish will be kept, as it is almost impossible to catch them, without removing rocks from the tank. Sometimes it is possible to entice them to hide somewhere, where they can be caught, i.e. a hollow stone. In a large aquarium where a Damselfish has its own territorium, this is a much smaller problem.
Damsels are placed in the genera; Abudefduf, Amblyglyphidodon, Amblypomacentrus, Cheiloprion, Chrysiptera, Dischistodus, Hemiglyphidodon, Hypsypops, Lepidozygus, Mecaenichthys, Microspathodon, Neoglyphidodon, Neopomacentrus, Nexilosus, Parma, Plectroglyphidodon, Pomacentrus, Pomachromis, Pristotis, Similiparma, Stegastes and Teixeirichthys.
|Distribution||Indo-Pacific: most islands of Oceania except Hawaiian Islands, Marquesas, and Pitcairn Group; also Australia north to the Ryukyu Islands. In the Indian Ocean, there are confirmed records Seychelles, Thailand and Western Australia. Often confused with <|
|English common names||
Black -axil chromis
Tea Yi Kai. 2014. Reef Nuggets 1: Damsels in disguise - Reef Builders - (English)
Henry C. Schultz. 2003. Friendly Damsels? It Can't be Possible!… The Genus Chromis - Reefkeeping Magazine - (English)
Scott W. Michael. 2008. Damselfishes & Anemonefishes (Reef Fishes) - TFH Publications / Microcosm Ltd. - (English)
James W. Fatherree. 2011. Aquarium Fish: Damselfishes and Chromises: the Good and the Bad - Advanced Aquarist - (English)
Bob Fenner. The Damsel and Anemonefishes, Family Pomacentridae - Wet Web Media - (English)
"Minimum volume" indicates the size of the tank needed to house this species under optimal conditions.
This is based on a medium size animal, which you want to keep for several years.
It might be possible to keep smaller specimens for a limited period in a smaller tank. A larger tank might be needed for fully-grown specimens.
"Hardiness" indicates how resistant this species is to disease and how well i tolerates bad conditions in general.
Some species doesn't handle transportation very well, but that doesn't mean that the species isn't hardy under the right conditions.
In this case, a "normal" aquarium is a reef aquarium with mixed corals or a fish only aquarium with an approximately salinity of 1.026 (sg) and a temperature close to 26°C.
Species requiring more than a 4000-liter tank are considered not suitable for home aquarium.
Special aquariums may cover tanks with low salinity, sub-tropical temperature, deep sand bed, sea grass etc.
Always reef safe: No sources indicate that this species will harm corals or other invertebrates.
Often reef safe: Only a few aquarists has reported problems keeping this species with corals and other invertebrates.
Reef safe with caution: This species may be a threat to some types of invertebrates.
Reef safe with luck: Most specimens will harm corals and/or other invertebrates, but you might be lucky.
Not reef safe: This species is a threat to most corals and/or other invertebrates.