La Plata eartheater

Gymnogeophagus australis

Also known as Australis gymnogeophagus

FreshwaterFish

Care at a glance

Temperature: 61–79°F (16–26°C)
pH: 6.5–7.8
Adult size: 6.1 in (15.5 cm)
Minimum tank: 66 gal (250 L)
Temperament: Mostly peaceful
Social behavior: Social
Swim level: Bottom
Difficulty: Medium
Breeding: Medium
Rarity: Rare
Origin: La Plata basin, Argentina and Uruguay
Family: Cichlidae

Overview

A temperate eartheater that is happiest in a small group of its own kind rather than kept singly, so aim for four or more and let them settle a loose pecking order. It spends its day over the bottom, taking mouthfuls of sand and sifting out food, and it is peaceful enough to share a tank with other calm, similarly sized fish. Feed sinking foods it can pick from the substrate, and include some frozen invertebrates. A group wants a long tank of about 250 liters or more with plenty of open sand to work.

In the wild

Gymnogeophagus australis comes from the La Plata basin near the latitudes of Buenos Aires, in temperate rivers that cool sharply in the southern winter. Give it a deep bed of soft sand it can sift without scratching its gills, some wood and smooth rock, and moderately soft to neutral water at a pH of 6.5 to 7.8. The key is temperature: let it run cooler, anywhere from about 16 to 26 C across the year, rather than holding it at steady tropical heat.

Good to know

This is a South American eartheater in the family Cichlidae, reaching about 15.5 centimeters. It is one of the southernmost members of its genus, adapted to seasonal water far cooler than most cichlids tolerate. Gymnogeophagus species are mouthbrooders, and this one breeds at medium difficulty, often keying its spawning to the warming of spring. A seasonal cool period actually helps condition it for breeding.

Did you know

Its home rivers can drop into the low teens Celsius in winter, cold enough to kill many tropical fish, so this is one of the few cichlids you keep in an unheated tank and reward with a genuine change of seasons.

Tank mates

La Plata eartheater is a mostly peaceful, social species that keeps to the bottom. These picks match on water type, temperature, pH, size and temperament.