Bolivian ram
Larger, plainer and vastly more forgiving than the German blue ram — tolerant of ordinary temperatures and ordinary tap water, and long-lived with it. The dwarf cichlid to start with.
Quick profile
- Scientific name
- Mikrogeophagus altispinosus
- Adult size
- 7–9 cm (2.8–3.5 in)
- Lifespan
- 4–6 years
- Temperature
- 22–28 °C (72–82 °F)
- pH
- 6–7.8
- Hardness
- 2–15 °dGH
- Minimum tank
- 110 L (29 US gal)
- Minimum length
- 80 cm
- Swimming zone
- Bottom
- Social
- Pair
- Diet
- Omnivore
- Overall confidence
- high confidence
What keeping this species involves
Hardy across normal community temperatures and hardness, unlike its more colourful relative.
Shallow, sandy, slow-flowing tributaries and pools.
Identity and names
- Common name
- Bolivian ram
- Scientific name
- Mikrogeophagus altispinosus
- Family
- Cichlidae
- Order
- Cichliformes
- Class
- Actinopterygii
Adult size and growth
7–9 cm (2.8–3.5 in)
Typical lifespan in an aquarium: 4–6 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 pair holding a substrate territory, with the tank space for other fish to stay out of it.
Temperature (°C)
Scale: 0 to 36 °C.
pH (pH)
Scale: 4 to 9.5 pH.
Hardness (°dGH)
Scale: 0 to 30 °dGH.
Where these figures come from
Habitat class
Lowland floodplain
Seasonally inundated flat country — várzea, chaco, swamp margin — where the water body changes size, depth and chemistry through the year.
The habitat's defining feature is change, so a single band describes it badly. Species from here are generally tolerant of a wide range and intolerant of nothing much — which makes them easy to keep and easy to keep wrongly.
- Conductivity
- 40–300 µS/cm
- Flow
- still
- Dissolved oxygen
- low
- 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.
- TemperatureFollows the habitat this animal comes from
- Follows the water this animal is recorded from — lowland floodplain. Lowland floodplain generally runs 22–32°C, and the advised band of 22–28°C is consistent with it. This is AquariumHQ's reasoning from the habitat, not a measurement of the species. A source does publish a figure for this parameter, and it answers a different question — an environmental range or a laboratory tolerance rather than a keeping recommendation. It is held alongside this band rather than behind it.
- pHFollows the habitat this animal comes from
- Follows the water this animal is recorded from — lowland floodplain. Lowland floodplain generally runs 6–7.5, and the advised band of 6–7.8 is consistent with it. This is AquariumHQ's reasoning from the habitat, not a measurement of the species.
- General hardnessFollows the habitat this animal comes from
- Follows the water this animal is recorded from — lowland floodplain. Lowland floodplain generally runs 2–12 dGH, and the advised band of 2–15 dGH is consistent with it. This is AquariumHQ's reasoning from the habitat, not a measurement of the species.
Scale: 20.5 to 33.5 °C.
Scale: 5.7 to 8.1 pH.
Scale: 0.1 to 17 dGH.
| Requirement | Value | Notes |
|---|---|---|
| Temperature | 22–28 °C (72–82 °F) | Stability matters more than hitting an exact figure. |
| pH | 6–7.8 | A stable pH outside the ideal band is usually better than an unstable one inside it. |
| General hardness | 2–15 °dGH | Check your supplier's published figure before choosing species. |
| Minimum volume | 110 L (29 US gal) | A floor, not a recommendation. |
| Minimum footprint | 80 cm long | A pair holding a substrate territory, with the tank space for other fish to stay out of it. |
| Water flow | low | Match the outflow to this rather than to the filter's rating. |
| Lid required | Recommended | Reduces evaporation and prevents accidents. |
| Structure | Fine sand, flat stones and cover. |
Behaviour
- Sifts mouthfuls of sand constantly — sharp gravel prevents the behaviour and damages the mouth.
Telling males from females
Males are larger with more extended fin filaments; sexing juveniles is unreliable.
Feeding
- Diet type
- Omnivore
- Staples
- Frozen bloodworm and daphnia, Sinking granules, Live foods
Breeding
- Strategy
- Substrate spawner; both parents guard
- Difficulty
- straightforward
- Parental care
- guarding
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 | low | 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 | none | Tough species such as Anubias and Java fern survive most grazers. |
Assessed pairings
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.
- Needs sand. This is a functional requirement, not an aesthetic one.
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
- Upper Madeira basin — Bolivia and western Brazil
- Habitat
- Shallow, sandy, slow-flowing tributaries and pools.
What the checklists say
8 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 | 4 | 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 | Mikrogeophagus altispinosus | Observed / measured | high confidence | Catalogue of Life; GBIF — Global Biodiversity Information Facility |
| native range | Upper Madeira basin — Bolivia and western Brazil | Observed / measured | moderate confidence | GBIF — Global Biodiversity Information Facility |
| adult size | 7–9 cm | Aquarium-literature consensus | high confidence | AquariumHQ husbandry synthesis |
| lifespan | 4–6 years | Aquarium-literature consensus | high confidence | AquariumHQ husbandry synthesis |
| temperature | 22–28 °C | Aquarium-literature consensus | high confidence | AquariumHQ husbandry synthesis |
| ph | 6–7.8 pH | Aquarium-literature consensus | high confidence | AquariumHQ husbandry synthesis |
| general hardness | 2–15 °dGH | Aquarium-literature consensus | high confidence | AquariumHQ husbandry synthesis |
| minimum tank volume | ≥ 110 L | AquariumHQ editorial position | moderate confidence | AquariumHQ husbandry synthesis |
| minimum tank length | ≥ 80 cm | 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 2026-08-11. 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. 8 distribution statements held from GBIF checklists — native in 2, 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 sizeOne sourceBased on a verified authoritative source.1 citation, 1 independent origin
A single source: clofsca-2003.
- 5.6 cm — FishBase · Maximum recorded · The range the species is recorded from · checked 2026-08-11
What this kind of claim needs: size a well-kept specimen reaches — no external source is required, provided AquariumHQ shows its reasoning. One authoritative source, which is what this kind of claim requires. Independent replication would be welcome and is not the standard.
What would improve this: Corroborate against a second, independent source.
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.
temperatureOne sourceAquariumHQ's own position, derived from evidenced inputs.1 citation, 1 independent origin
A single source: aquarien-atlas.
- 22–26 °C — FishBase · Tolerated range · The range the species is recorded from · checked 2026-08-11
What this kind of claim needs: what aquariumhq advises for keeping — no external source is required, provided AquariumHQ shows its reasoning. Derived from the observed range rather than copied from it. AquariumHQ advises 22–28 °C; FishBase records 22–26 °C. Lower bounds agree. The Bolivian ram is the cooler-water species of the two rams and the advice already reflects that; two degrees of headroom at the top is ordinary keeping latitude.
What would improve this: Corroborate against a second, independent source.
phPublished with one end of the range missingAquariumHQ's own position, derived from evidenced inputs.
A source published one end of the range and left the other unstated.
At least 7 pH — the source does not state an upper boundFishBase gives the pH range as "7.0 - ?". The lower bound is published and the upper is not, so this is recorded as a constraint — at least pH 7.0 — rather than completed with an invented ceiling.
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: Find a source that publishes the missing bound. Do not infer it.
general hardnessPublished with one end of the range missingAquariumHQ's own position, derived from evidenced inputs.
A source published one end of the range and left the other unstated.
At least 10 dGH — the source does not state an upper boundFishBase gives the dH range as "10 - ?". The lower bound is published and the upper is not, so this is recorded as a constraint — at least 10 dGH — rather than completed with an invented ceiling.
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: Find a source that publishes the missing bound. Do not infer it.
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.
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.
- The kinds of water aquarium fish come fromThis record's water bands follow lowland floodplain, which is the kind of water this animal is recorded from.
- 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
Kept as a pair or singly; pairs form readily from a group of juveniles.