Geophagus altifrons Breeding Guide

How to breed Geophagus altifrons, an Amazon eartheater; a substrate-spawning, ovophilous biparental mouthbrooder that lays on a flat surface then mouthbroods the eggs.

Overview

Geophagus altifrons is a large, peaceful eartheater of the middle-to-lower Amazon basin, recorded by Seriously Fish from tributaries including the Tapajos, Xingu, Trombetas, Madeira, Negro and Purus. Seriously Fish describes it as a substrate-spawning, ovophilous, biparental mouthbrooder that has been bred on numerous occasions in aquaria. It is best kept in a group so a pair can form naturally.

Sexing

According to Seriously Fish, sexing is very difficult, with no external differences except during spawning when the ovipositor of the female is visible. The practical approach is to raise a group of juveniles and allow pairs to form.

Conditioning

As an omnivorous sand-sifter, the species is conditioned on a varied diet. A group in a large, sandy-bottomed tank with stable, warm, soft water encourages pair formation, after which a bonded pair will defend a spawning territory.

Breeding Setup

Provide a flat rock or driftwood as a spawning surface over a sand substrate. Seriously Fish reports breeding-suitable conditions of 26-32 C and pH 4.8-6.6 for wild fish, while noting that captive-bred specimens accept neutral conditions; fry develop at around 25-28 C.

Spawning Behavior & Trigger

Seriously Fish describes subtle courtship involving fin flaring, circling, gaping and head-jerking. Spawning occurs in typical substrate-spawning fashion, with the female laying rows of eggs that the male fertilises, repeated over several hours; maximum brood size is around 200 eggs. Warm, soft water and a well-conditioned pair are the practical triggers.

Egg & Fry Care

Being ovophilous, the parents take the eggs into the mouth. Seriously Fish notes the pair may mouthbrood simultaneously or exchange the entire brood roughly daily. At 25-28 C fry become free-swimming at 8-11 days, when the parents begin releasing them to feed, cautiously at first; fry accept powdered dry foods, Artemia nauplii and microworm.

Common Challenges

Sexing difficulty makes group rearing essential. Seriously Fish notes some males become aggressive after spawning and may drive the female away, so providing space and cover helps protect the holding parent and the brood.