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FishfreshwaterModerate

Macmaster's dwarf cichlid

A savannah Apistogramma rather than a forest one, and correspondingly less dependent on extreme blackwater than the Rio Negro species. Males carry a red-edged caudal that gives the trade name and deepen to near-crimson when holding ground.

Quick profile

Scientific name
Apistogramma macmasteri
Adult size
6–8 cm (2.4–3.1 in)
Lifespan
3–5 years
Temperature
23–28 °C (73–82 °F)
pH
5.5–7.2
Hardness
1–10 °dGH
Minimum tank
75 L (20 US gal)
Minimum length
70 cm
Swimming zone
Bottom
Social
Harem
Diet
Micropredator
Overall confidence
moderate confidence

What keeping this species involves

More tolerant of moderately hard water than the blackwater Apistogramma, and correspondingly more likely to breed in an ordinary soft-water tank.

Shallow, shaded, sandy-bottomed streams over leaf litter.

Identity and names

Common name
Macmaster's dwarf cichlid
Scientific name
Apistogramma macmasteri
Family
Cichlidae
Order
Cichliformes
Class
Actinopterygii
Also sold as
red-neck apisto, Apistogramma macmasteri, Villavicencio dwarf cichlid

Adult size and growth

6–8 cm (2.4–3.1 in)

Typical lifespan in an aquarium: 3–5 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.

Water and tank requirements

A male's territory with a defensible cave for each female inside it. Floor area sets this, not water volume.

RequirementValueNotes
Temperature23–28 °C (73–82 °F)Stability matters more than hitting an exact figure.
pH5.5–7.2A stable pH outside the ideal band is usually better than an unstable one inside it.
General hardness1–10 °dGHCheck your supplier's published figure before choosing species.
Minimum volume75 L (20 US gal)A floor, not a recommendation.
Minimum footprint70 cm longA male's territory with a defensible cave for each female inside it. Floor area sets this, not water volume.
Water flowlowMatch the outflow to this rather than to the filter's rating.
Lid requiredRecommendedReduces evaporation and prevents accidents.
StructureSand, caves and leaf litter with broken sightlines at the base.

Group size and social behaviour

Harem-forming where every female can defend a cave. Without enough caves the dominant female evicts the rest.

Structure
Harem
Sex ratio
One male to two or three females, each with her own cave.

Behaviour

  • Works the sand in short hops between cover.
  • A guarding female drives much larger fish away from her cave mouth.

Telling males from females

Males are larger with red caudal margins and extended dorsal spines; females turn yellow-black when guarding.

Feeding

Diet type
Micropredator
Staples
Frozen bloodworm, cyclops and daphnia, Live blackworm, Small sinking dry foods

Breeding

Strategy
Cave spawning with maternal brood care
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.

Risk this species poses to common tankmates
TowardsRiskWhat it means
Small fishlowAnything that fits in the mouth is at risk once this species reaches adult size.
Adult dwarf shrimpmoderateCover reduces losses but rarely prevents them where the risk is high.
ShrimpletshighDetermines whether a shrimp colony can grow rather than merely persist.
SnailslowApplies to snails you wanted as well as snails you did not.
Long or trailing finsoccasionalFin damage is an entry point for secondary infection.
PlantsnoneTough 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.

  • A guarding female will not tolerate a corydoras near her cave, which is where most mixed bottom-dweller problems start.
  • Sold as a beginner's dwarf cichlid on the strength of hardiness rather than of temperament.

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 Meta drainage of the Colombian llanos
Habitat
Shallow, shaded, sandy-bottomed streams over leaf litter.

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.

StatusPlacesWhat this means
Native1A checklist states the species occurs here naturally.
Introduced1A 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 stated6The 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.

ClaimValueEvidence typeConfidenceSource
scientific nameApistogramma macmasteriObserved / measuredhigh confidenceCatalogue of Life; GBIF — Global Biodiversity Information Facility
native rangeUpper Meta drainage of the Colombian llanosObserved / measuredmoderate confidenceGBIF — Global Biodiversity Information Facility
adult size6–8 cmAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
lifespan3–5 yearsAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
temperature23–28 °CAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
ph5.5–7.2 pHAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
general hardness1–10 °dGHAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
minimum tank volume≥ 75 LAquariumHQ editorial positionmoderate confidenceAquariumHQ husbandry synthesis
minimum tank length≥ 70 cmAquariumHQ editorial positionmoderate confidenceAquariumHQ 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 2026-08-12. 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 1, introduced in 1 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.