Brown Chromis Breeding Guide

Breeding Chromis multilineata: a Caribbean demersal nest spawner where the male tends a substrate nest, the female deposits adhesive eggs, and the male guards them until tiny pelagic larvae hatch.

Overview

Chromis multilineata (listed by FishBase as Azurina multilineata) ranges through the Western Atlantic from Florida and Texas across the Caribbean to Brazil, with eastern Atlantic populations at St Helena, Ascension and Sao Tome, and grows to about 20 cm. It forms diurnal feeding schools over reef tops, rising to feed mainly on copepods. FishBase records it as oviparous with distinct pairing, demersal eggs adhering to the substrate, and males that guard and aerate the eggs. IUCN status is Least Concern.

Sexing

External sexual differences are slight outside spawning, so the sexes are told apart chiefly by role during reproduction. The male occupies and maintains the nest territory, and the female is the fish that approaches to lay; pairs form within the larger feeding school. Starting from a group rather than forcing a pair improves the odds of a natural, compatible pairing.

Conditioning

A well-fed school in stable reef water reaches condition when offered frequent small meals of planktonic and meaty foods. As its natural feeding is concentrated on copepods taken above the reef, several daily feedings of fine zooplankton-type foods most closely match the diet documented on FishBase and support egg development.

Breeding Setup

Following the pomacentrid pattern the male clears algae and invertebrates from a patch of hard substrate to form a nest, so the system should offer exposed flat rock within a defensible area. Brown Chromis can be kept in larger groups, and a spacious tank lets the school maintain structure while a male holds and prepares its nest site.

Spawning Behavior & Trigger

Courtship in damselfishes is ritualised, with darting motions, chasing and fin spreading by the male near the nest. The female lays a layer of sticky eggs onto the cleared substrate while the male follows and fertilises them externally. FishBase records distinct pairing during breeding for this species.

Egg & Fry Care

The demersal eggs stick to the substrate and are guarded and aerated by the male. In Pomacentridae generally, incubation takes about two to seven days, after which larvae of roughly 2 to 4 mm hatch into a pelagic phase that may last from about a week to more than a month. The first-feeding larvae need very small live plankton such as cultured copepods.

Common Challenges

As with other chromis, the bottleneck is rearing the minute pelagic larvae, which require dense cultures of appropriately sized live plankton beyond what a typical display tank provides. Species-specific larval rearing has not been documented, so home efforts usually succeed only up to the point of hatching.