Care
Green Chromis are found in large shoals in the wild, generally associated with branching hard corals such as Acropora. As their planktonic prey is swept to them in these areas of brisk water movement, they can be relaxed about resources and enjoy protection from predators amongst the branching coral thickets. This makes them amongst the most peaceful of the notorious damselfish family.
Being a relatively peaceful social species, Chromis should be kept in groups of 6 or more. These active fish spend a lot of time out in the water column, in turn acting as "dither fish", encouraging more reclusive species out into the open and encouraging other plankton feeders to try a range of prepared diets that more finicky fishes may not recognise as food. Single specimens may pine away in the corners of the tank or become harassed by other tankmates; indeed, keeping this sociable species in this way could be considered cruel. As with any damselfish, groups are most stable when a single larger dominant fish is added alongside smaller specimens - this larger fish will rapidly become a territorial dominant male, even if this means a change of current gender. This mimics the situation seen in nature and stops individuals fighting over the top spot. Multiple males can coexist in large set ups if numbers are high and each has access to a spawning territory.
Green Chromis are generally peaceful, relatively hardy, and are considered a good beginner's fish. Tankmates should be of a peaceful nature, although larger territorial species such as tangs and angelfish seldom see them as a threat.
A similar species, the Black-axil chromis (C. atripectoralis) can be easily mistaken for the Green chromis and differs in having a dark spot at the base of the pectoral fin.
Feeding
Offer a varied diet consisting of a dry food staple together with small frozen foods such as Spirulina-enriched brineshrimp, Mysis shrimp and finely chopped krill, plus marine flake food and herbivore rations. Feed small amounts 3 times per day. Enriching your frozen foods with liquid vitamin products prior to feeding will help your fish to retain their bright colours.
Breeding
This species has been known to spawn in the home aquarium. The male is said to establish a breeding site before trying to entice individual females into his domain. The male fish guards the eggs, which may be deposited in a substrate pit, on top of algae clumps or even on the glass. Eggs are said to number several hundred and depending on temperature of the water, will hatch within 48-72 hours.
