Copadichromis trewavasae Breeding Guide

How to breed Copadichromis trewavasae, a small open-water utaka hap from Lake Malawi: utaka feeding, sexing, harem setup and three-week maternal mouthbrooding.

Overview

Copadichromis trewavasae is a haplochromine cichlid endemic to Lake Malawi, where it is widespread and also recorded from the Malawian, Mozambican and Tanzanian waters of the lake. It belongs to the group of open-water species known as utaka. The species was described by Konings in 1999 and is named after the ichthyologist Ethelwynn Trewavas. It is listed as Least Concern on the IUCN Red List. In the Aquairi knowledge base it is recorded at 12-14 cm, making it one of the smaller display haps.

Sexing

The genus Copadichromis shows the sexual dimorphism typical of Lake Malawi haplochromines: dominant males develop intense nuptial colour while females remain plainer. In this species males are metallic blue and females carry yellowish fins. Because mature males hold and defend territories, the most reliable cue is behaviour combined with the brighter male colour.

Conditioning

Copadichromis trewavasae feeds by picking particles out of the water column, a planktivorous utaka strategy. To bring fish into spawning condition, offer small, frequent meals built around the kinds of zooplankton-like foods that match this feeding mode. Stable rift-lake water chemistry supports conditioning.

Breeding Setup

As a relatively peaceful utaka, the species is best kept and spawned as a group with several females per male so that male attention is spread across the group. Provide open water above a sand substrate; the species is often found over sediment-rich, muddy bottoms in the lake. A large tank is needed because this is a non-territorial open-water swimmer that uses the full volume.

Spawning Behaviour & Trigger

Like other members of the genus, Copadichromis trewavasae is a maternal mouthbrooder. A receptive female lays eggs that the male fertilises, after which she collects them into her mouth. Good conditioning and stable warm rift-lake conditions are the usual triggers for spawning.

Egg & Fry Care

The female incubates the developing eggs and larvae in her buccal cavity, as is universal for Lake Malawi haplochromines, typically for around three weeks before the free-swimming fry are released. A brooding female should not be disturbed, as stress can cause her to release or swallow the brood prematurely.

Common Challenges

The main difficulty is providing enough open swimming space for a shoaling open-water species, and maintaining the firm, alkaline, mineral-rich water of Lake Malawi. As with all maternal mouthbrooders, holding females may stop feeding while incubating and lose condition, so they should be well fed beforehand.