Blue-green chromis

Geographic Origin and Biotope: Very common throughout the Indo-Pacific (from the Red Sea to Japan and Polynesia). Forms gigantic schools above branching corals (Acropora) in protected lagoons.

Taxonomy and Morphology: Blue Green Chromis (Chromis viridis). Marine fish of the Pomacentridae family (Damselfish). Reaches 10 cm (4 inches). Almond shape, agile and responsive body.

Social Behavior: Schooling species par excellence in the marine reef. Extremely lively. To avoid aggression among conspecifics (the alpha male can decimate the group) it must be added in an odd number of at least 7-9 specimens.

Coloration and Sexual Dimorphism: Stunning metallic iridescence that changes from mint green to sky blue depending on the angle of light. During reproduction the male assumes a pale yellow coloration and becomes aggressive.

Aquarium Setup: Marine aquarium of at least 200 liters (55 gallons) developed in length. Vital space for free swimming at the top. Branching coral formations (or rocks) into which they will dive at the slightest danger are indispensable.

Diet and Feeding: Planktivorous omnivore. In nature they eat zooplankton in the current. In the tank they are greedy and devour mysis, brine shrimp, marine granules and algae flakes. Must be fed 2-3 times a day.

Water Quality: Pure tropical marine (SG 1.024-1.026). Requires strong water current created by wavemakers: Chromis love to swim against the current all day.

Compatibility and Tankmates: Totally "Reef-Safe". Does not bother corals or invertebrates. Ideal for adding movement to marine tanks (dither fish) with angelfish, tangs or clownfish. Avoid predators (e.g. lionfish).

Aquarium Reproduction: Possible in large mature marine aquariums. The male prepares a spawning site on the sand or rock, the female lays and the male guards the eggs. Hard to wean the microscopic pelagic fry.

Risks and Diseases: Sensitive to Uronema marinum post-importation (lethal red spots). In small aquariums, without currents or with small schools (3-4 fish), they will kill each other due to hierarchical stress.