Snuppet fra
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For their size, these angels can be downright feisty; in particular the "smallest of the small", those Centropyge that rarely exceed 2 1/2" (C. acanthops, C. argi, C. aurantonotus, C. fisheri, C. flavicauda, C. nigriocellus, C. resplendens). All dwarf angels are territorial, especially with members of their own species, then other Centropyge. Only folks with very big systems, four or more feet long, should tempt fate with more than one of the same species... and then only with plenty of cover and their watchful eye.
As regards their use in reef set-ups, I have seen this done successfully with several species, and just about equally turn into a disaster. Dwarf angels will sample live corals and other invertebrates as well as micro and macro-algae. Before attempting one, keep in mind how difficult a pygmy angel will be to remove should it turn into a nibbler in your reef. Still not dissuaded? If you must, try one of the dwarf-dwarf species or a very small individual of a full size model.