TankBud

Paraguay eartheater

Gymnogeophagus balzanii

Also known as Argentine humphead, Humpheaded eartheater

FreshwaterFish

Paraguay eartheater (Gymnogeophagus balzanii)
Imperial Tropicals · Used with permission

Care at a glance

Temperature
70–77°F
21–25°C
pH
6.5–7.5
Adult size
5.5 in
14 cm
Minimum tank
37 gal
140 L
Temperament
Aggressive
Social behavior
Solitary
Swim level
Middle
Difficulty
Medium
Breeding
Mouthbrooder · Medium
Rarity
Rare
Family
Cichlidae
Origin
Uruguay, Brazil, Paraguay, Argentina

Overview

The Paraguay eartheater is a stocky, sand-sifting cichlid for a roomy tank. It is a step up from the easiest fish.

Did you know

The Paraguay eartheater is a delayed mouthbrooder. The pair spawns on the substrate, and only after a day or two does the female take the eggs and larvae into her mouth.

Caring for the Paraguay eartheater

Give a Paraguay eartheater at least 37 gal (140 L), so it has room to forage and hold a territory. It takes mouthfuls of sand and sieves out food, so it needs a soft sandy floor that will not harm it. Add some smooth rocks and driftwood, a few hardy plants and open swimming space.

Keep the tank on the cooler side of tropical, at 70 to 77°F (21 to 25°C), with a seasonal drop rather than constant heat. Give it neutral water, moderately soft to slightly hard, with a pH of 6.5 to 7.5. Feed sinking pellets and frozen foods such as bloodworm and brine shrimp.

It is fairly territorial, especially between males, so keep a single fish or one male with a couple of females in a larger tank. It can be pushy at spawning time, but it is not a relentless killer. Choose robust, similarly sized tank mates that are not small enough to be seen as food.

Mature males grow a tall, rounded hump on the forehead, which gives the fish its other common name, the Argentine humphead. The female holds the brood in her mouth for a week or so, then releases free-swimming fry. She does not feed while holding, and her care continues for weeks after release. That makes it a rewarding species to breed, at medium difficulty.

Good to know

The Paraguay eartheater, Gymnogeophagus balzanii, is a member of the cichlid family, Cichlidae. It is unusual among eartheaters, since it is a maternal mouthbrooder rather than a simple substrate spawner like many of its relatives.

In the wild

The Paraguay eartheater comes from the Paraguay and Parana river systems across Uruguay, southern Brazil, Paraguay and northern Argentina. The range is subtropical with real seasons, so the fish lives through a cooler winter.

Common questions

What size tank does a Paraguay eartheater need?

A Paraguay eartheater needs at least 37 gal (140 L). It spends most of its time in the middle.

What temperature and pH does a Paraguay eartheater need?

A Paraguay eartheater is comfortable at 70–77°F (21–25°C) with a pH of 6.5–7.5.

What does a Paraguay eartheater eat?

A Paraguay eartheater eats sinking pellets and frozen foods such as bloodworm and brine shrimp. It also sieves food from mouthfuls of sand.

How big does a Paraguay eartheater get?

An adult Paraguay eartheater reaches about 5.5 in (14 cm).

How can you tell a male Paraguay eartheater from a female?

Males grow a tall, rounded hump on the forehead as they mature.

How does a Paraguay eartheater breed?

Paraguay eartheaters are maternal mouthbrooders. The female holds the brood in her mouth for a week or so, then releases free-swimming fry and keeps caring for them for weeks. Breeding them is of medium difficulty.

Related species