Green Chromis

Chromis viridis

Also known as Blue-Green Chromis, Blue Green Reef Chromis, Green Reef Chromis

SaltwaterFish

Green Chromis (Chromis viridis) — (c) Debra Baker, some rights reserved (CC BY) · CC BY 4.0

Care at a glance

Temperature: 75–82°F (24–28°C)
pH: 8.1–8.4
Adult size: 3.1 in (8 cm)
Minimum tank: 30 gal (115 L)
Temperament: Peaceful
Social behavior: Schooling
Swim level: Middle
Difficulty: Easy
Breeding: Hard
Rarity: Very common
Reef safe: Reef safe
Origin: Indo-Pacific
Family: Pomacentridae

Overview

A peaceful, active schooling fish and one of the easiest ways to add constant movement to a reef tank. It is best kept in a group of six or more, since larger groups spread out aggression and keep the school tight. In small groups or crowded tanks the fish can form a pecking order and pick each other off one by one, so a generous group and open swimming space matter. Feeds readily on frozen and prepared foods and does not bother corals.

In the wild

Forms large aggregations above branching Acropora and other staghorn corals in shallow lagoons and reef flats across the Indo-Pacific. Whole shoals hover just above the coral, feeding on drifting plankton and dropping into the branches for shelter the instant a predator appears. Its shimmering blue-green color comes from the way light scatters across its body.

Good to know

Chromis viridis is a planktivorous damselfish that spawns on the reef, where the male tends a nest of demersal eggs laid on a cleared patch of substrate. Unlike clownfish, its larvae are tiny and drift in the plankton, which is why captive breeding has historically been very difficult.

Did you know

Green chromis kept in groups that are too small often dwindle over time as a dominant individual bullies the others, which is why experienced keepers deliberately start with a larger shoal.