Redhump eartheater
The smallest and hardiest of the commonly kept eartheaters, and the only one that mouthbroods rather than guarding a substrate clutch. Males develop a red fatty hump on the forehead and are considerably larger than females, which makes a harem the natural arrangement.
Quick profile
- Scientific name
- Geophagus steindachneri
- Adult size
- 12–18 cm (4.7–7.1 in)
- Lifespan
- 6–10 years
- Temperature
- 24–29 °C (75–84 °F)
- pH
- 6–7.5
- Hardness
- 3–15 °dGH
- Minimum tank
- 250 L (66 US gal)
- Minimum length
- 120 cm
- Swimming zone
- Bottom
- Social
- Harem — at least 4
- Diet
- Omnivore
- Overall confidence
- moderate confidence
What keeping this species involves
One of the easier large South American cichlids: adaptable in water, straightforward to feed and not especially aggressive. The absolute requirement is deep fine sand.
Sandy-bottomed rivers and streams with moderate current, in soft to moderately hard water.
Identity and names
- Common name
- Redhump eartheater
- Scientific name
- Geophagus steindachneri
- Family
- Cichlidae
- Order
- Cichliformes
- Class
- Actinopterygii
- Also sold as
- Geophagus steindachneri, Geophagus hondae, redhump geophagus, Colombian eartheater
Adult size and growth
12–18 cm (4.7–7.1 in)
Typical lifespan in an aquarium: 6–10 years. Almost every animal sold in a shop is a juvenile, so the tank has to suit the size in the first line rather than the size in the bag.
Shape, which is what the compatibility engine reads instead of length alone: deep-bodied with a moderate. Assigned from what is typical of Cichlidae, not examined for this species.
Water and tank requirements
A sand-sifting fish that works its way across the floor in long passes. Floor area is the requirement and height contributes nothing.
Temperature (°C)
Scale: 0 to 36 °C.
pH (pH)
Scale: 4 to 9.5 pH.
Hardness (°dGH)
Scale: 0 to 30 °dGH.
Why these ranges: Magdalena basin rivers, which are softer than Central American waters and less extreme than Amazonian blackwater. The species is genuinely adaptable within this band, which is why it is the eartheater most often recommended first.
Where these figures come from
Habitat class
Clearwater lowland river
Transparent, mineral-poor rivers draining ancient shield geology — the Tapajós and Xingu type — with low sediment and good light penetration.
Soft water with more movement and more oxygen than a forest stream. Species from here generally want current and open swimming room as much as they want the chemistry.
- Conductivity
- 20–100 µS/cm
- Flow
- moderate
- Dissolved oxygen
- near saturation
- Seasonality
- strong
These are figures for the KIND of water body, not measurements of this species. They are AquariumHQ’s summary of the general limnology and are given wide because the water is.
- TemperatureReasoned on this record
- This record states its own reason for this band. See the water section.
- pHReasoned on this record
- This record states its own reason for this band. See the water section.
- General hardnessReasoned on this record
- This record states its own reason for this band. See the water section.
| Requirement | Value | Notes |
|---|---|---|
| Temperature | 24–29 °C (75–84 °F) | Stability matters more than hitting an exact figure. |
| pH | 6–7.5 | A stable pH outside the ideal band is usually better than an unstable one inside it. |
| General hardness | 3–15 °dGH | Check your supplier's published figure before choosing species. |
| Minimum volume | 250 L (66 US gal) | A floor, not a recommendation. |
| Minimum footprint | 120 cm long × 45 cm deep | A sand-sifting fish that works its way across the floor in long passes. Floor area is the requirement and height contributes nothing. |
| Water flow | moderate | Match the outflow to this rather than to the filter's rating. |
| Lid required | Recommended | Reduces evaporation and prevents accidents. |
| Structure | Deep fine sand across the whole floor, with wood and rounded stone as boundaries. The sand is the habitat. |
Behaviour
- Takes a mouthful of sand, chews it and expels a plume through the gills, moving forward a body length between mouthfuls.
- Males court by quivering over the sand and leading females to a cleared patch, repeatedly and at length.
Telling males from females
Males reach half again the female's length and develop a red fatty hump on the head. Females stay smaller, plainer and without the hump.
Feeding
Takes mouthfuls of sand and sorts them for invertebrates and organic matter. Sinking food is essential; anything that stays at the surface is missed entirely.
- Diet type
- Omnivore
- Staples
- Sinking cichlid pellets, Frozen mysis, Frozen bloodworm, Frozen brine shrimp
Breeding
- Strategy
- Maternal mouthbrooding after spawning on open sand
- Difficulty
- straightforward
- Parental care
- mouthbrooding
Unusual among Geophagus, most of which guard a substrate clutch or brood in a delayed fashion. This species takes the eggs up immediately.
Tankmates and compatibility
Assessments are derived from stored traits by the compatibility engine, with the reasoning shown. A verdict is a statement about probability, not a guarantee — individual temperament can override it.
| Towards | Risk | What it means |
|---|---|---|
| Small fish | moderate | Anything that fits in the mouth is at risk once this species reaches adult size. |
| Adult dwarf shrimp | high | Cover reduces losses but rarely prevents them where the risk is high. |
| Shrimplets | near-certain | Determines whether a shrimp colony can grow rather than merely persist. |
| Snails | low | Applies to snails you wanted as well as snails you did not. |
| Long or trailing fins | occasional | Fin damage is an entry point for secondary infection. |
| Plants | uproots | Tough species such as Anubias and Java fern survive most grazers. |
Any pair in the catalogue can be assessed with the compatibility checker.
Welfare considerations
Points where the way this species is commonly sold or kept differs from what it actually needs.
- Gravel substrate prevents the feeding behaviour entirely and coarse grit damages the gill filaments. This is the single most consequential decision when setting up for an eartheater.
- A lone female receives a male's full courtship, which is persistent enough to wear her down. The harem is not a preference here but a way of distributing it.
Problems to watch for
Most problems in a tank containing this species are general rather than species-specific. Start with the troubleshooting index and work from the observation rather than from a guess at the cause.
What AquariumHQ does not yet hold
Species-level disease susceptibility is modelled in the graph and is not yet populated. Health pages will not be published until each condition has veterinary sourcing, because health content written without evidence is the most harmful thing this product could publish. The gap is recorded in the coverage report.
Where it comes from
- Native range
- The Magdalena and Cauca drainages of Colombia
- Habitat
- Sandy-bottomed rivers and streams with moderate current, in soft to moderately hard water.
What the checklists say
11 distribution statements retrieved from GBIF checklists. Establishment means is reproduced from the source where it states one, and left unstated where it does not — a record of presence is not a record of origin.
| Status | Places | What this means |
|---|---|---|
| Native | 2 | A checklist states the species occurs here naturally. |
| Introduced | 2 | A checklist states the species arrived here with human help. That is not a statement that it is established, harmful or illegal. |
| Recorded as present, establishment means not stated | 7 | The source records the species as present and does not say whether it is native or introduced. AquariumHQ does not fill that in. |
Evidence
Every stored value with the kind of support behind it and where to check it. Evidence type and confidence are separate axes: an editorial position held confidently and a measurement held tentatively are different things.
| Claim | Value | Evidence type | Confidence | Source |
|---|---|---|---|---|
| scientific name | Geophagus steindachneri | Observed / measured | high confidence | Catalogue of Life; GBIF — Global Biodiversity Information Facility |
| native range | The Magdalena and Cauca drainages of Colombia | Observed / measured | moderate confidence | GBIF — Global Biodiversity Information Facility |
| adult size | 12–18 cm | Aquarium-literature consensus | moderate confidence | AquariumHQ husbandry synthesis |
| lifespan | 6–10 years | Aquarium-literature consensus | moderate confidence | AquariumHQ husbandry synthesis |
| temperature | 24–29 °C | Aquarium-literature consensus | moderate confidence | AquariumHQ husbandry synthesis |
| ph | 6–7.5 pH | Aquarium-literature consensus | moderate confidence | AquariumHQ husbandry synthesis |
| general hardness | 3–15 °dGH | Aquarium-literature consensus | moderate confidence | AquariumHQ husbandry synthesis |
| minimum tank volume | ≥ 250 L | AquariumHQ editorial position | moderate confidence | AquariumHQ husbandry synthesis |
| minimum tank length | ≥ 120 cm | AquariumHQ editorial position | moderate confidence | AquariumHQ husbandry synthesis |
| minimum group size | ≥ 4 | AquariumHQ editorial position | moderate confidence | AquariumHQ husbandry synthesis |
Last reviewed 2026-08-10. Values labelled as an aquarium-literature consensus are AquariumHQ editorial positions rather than measurements — see how evidence is handled.
Why we say this
What each figure on this page rests on, and how far that is from being independently established.
Every figure on this page has a provenance. Open any claim to see what AquariumHQ holds for it, which sources say what, and what a claim of that kind actually needs. Different claims need different evidence: an accepted scientific name is settled by one authority, while a legal restriction needs a current primary instrument. A single source is often the right answer rather than a thin one.
scientific nameAquariumHQ's own position, externally checkableBased on a verified authoritative source.
AquariumHQ's own position on a claim an external source could support.
What this kind of claim needs: accepted scientific name and classification — 1 authoritative source in an appropriate context. Checked against gbif on 2026-08-29. One authoritative backbone is what this class requires.
What would improve this: Go and read a source. This is reachable and has not been reached.
native rangeAquariumHQ's own position, externally checkableBased on a verified authoritative source.
AquariumHQ's own position on a claim an external source could support.
What this kind of claim needs: where the species occurs — 1 authoritative source in an appropriate context. 11 distribution statements held from GBIF checklists — native in 1, introduced in 2 countries. Establishment means is reproduced from the source, never inferred from occurrence.
What would improve this: Go and read a source. This is reachable and has not been reached.
adult sizeAquariumHQ's own position, externally checkableAquariumHQ's own position, derived from evidenced inputs.
AquariumHQ's own position on a claim an external source could support.
What this kind of claim needs: size a well-kept specimen reaches — no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.
What would improve this: Go and read a source. This is reachable and has not been reached.
lifespanAquariumHQ's own position, externally checkableAquariumHQ's own position, derived from evidenced inputs.
AquariumHQ's own position on a claim an external source could support.
What this kind of claim needs: what aquariumhq advises for keeping — no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.
What would improve this: Go and read a source. This is reachable and has not been reached.
temperatureAquariumHQ's own position, externally checkableAquariumHQ's own position, derived from evidenced inputs.
AquariumHQ's own position on a claim an external source could support.
What this kind of claim needs: what aquariumhq advises for keeping — no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.
What would improve this: Go and read a source. This is reachable and has not been reached.
phAquariumHQ's own position, externally checkableAquariumHQ's own position, derived from evidenced inputs.
AquariumHQ's own position on a claim an external source could support.
What this kind of claim needs: what aquariumhq advises for keeping — no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.
What would improve this: Go and read a source. This is reachable and has not been reached.
general hardnessAquariumHQ's own position, externally checkableAquariumHQ's own position, derived from evidenced inputs.
AquariumHQ's own position on a claim an external source could support.
What this kind of claim needs: what aquariumhq advises for keeping — no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.
What would improve this: Go and read a source. This is reachable and has not been reached.
minimum tank volumeAquariumHQ's judgement — no authority publishes thisAquariumHQ's own position, derived from evidenced inputs.
No external authority publishes this. The rationale carries the reasoning.
What this kind of claim needs: minimum tank size — no external source is required, provided AquariumHQ shows its reasoning. No authority publishes this. AquariumHQ derives it, and the derivation is recorded with its inputs and assumptions.
What would improve this: Keep the rationale current. There is no source to find.
minimum tank lengthAquariumHQ's judgement — no authority publishes thisAquariumHQ's own position, derived from evidenced inputs.
No external authority publishes this. The rationale carries the reasoning.
What this kind of claim needs: minimum tank size — no external source is required, provided AquariumHQ shows its reasoning. No authority publishes this. AquariumHQ derives it, and the derivation is recorded with its inputs and assumptions.
What would improve this: Keep the rationale current. There is no source to find.
minimum group sizeAquariumHQ's judgement — no authority publishes thisAquariumHQ's own position, derived from evidenced inputs.
No external authority publishes this. The rationale carries the reasoning.
What this kind of claim needs: group size — no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.
What would improve this: Keep the rationale current. There is no source to find.
Guides relevant to this species
Chosen from this record's own traits rather than listed on every page.
- Predator and prey sizeIt takes adult dwarf shrimp, which decides what can share the tank.
- Wild conditions and aquarium recommendationsThe water band on this page is an AquariumHQ position with a stated reason, not a measurement of a river.
- How to read a compatibility verdictThis animal is recorded as nipping fins, which is one of the few compatibility factors with real reports behind it.
Group size and social behaviour
Males compete and females do not. A single male with several females spreads his courtship, which is otherwise relentless towards whichever female is present.