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FishfreshwaterDemanding

Zebra acara

A blackwater dwarf cichlid marked with oblique dark bars, and one where the female is the more strikingly patterned of the pair. It is a pair-forming cave spawner rather than a harem species, which changes how a tank is stocked for it.

Quick profile

Scientific name
Nannacara adoketa
Adult size
6–9 cm (2.4–3.5 in)
Lifespan
3–5 years
Temperature
24–29 °C (75–84 °F)
pH
4.5–6
Hardness
0–4 °dGH
Minimum tank
75 L (20 US gal)
Minimum length
70 cm
Swimming zone
Bottom
Social
Pair
Diet
Micropredator
Overall confidence
low confidence

What keeping this species involves

Needs genuinely soft acidic water for anything past survival, and a guarding female needs tankmates that can leave her area.

Blackwater forest streams over deep leaf litter, very soft and strongly acidic.

Identity and names

Common name
Zebra acara
Scientific name
Nannacara adoketa
Family
Cichlidae
Order
Cichliformes
Class
Actinopterygii
Also sold as
Nannacara adoketa, Ivanacara adoketa, zebra dwarf cichlid
Former or synonymous names
Ivanacara adoketa

Adult size and growth

6–9 cm (2.4–3.5 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 pair holds ground around one cave; the footprint has to contain that plus somewhere the other fish can be.

Why these ranges: Rio Negro blackwater, which is genuinely among the softest and most acidic fresh water on earth. This band is a habitat statement rather than a comfort range — the fish will live above it and will not spawn.

RequirementValueNotes
Temperature24–29 °C (75–84 °F)Stability matters more than hitting an exact figure.
pH4.5–6A stable pH outside the ideal band is usually better than an unstable one inside it.
General hardness0–4 °dGHCheck your supplier's published figure before choosing species.
Minimum volume75 L (20 US gal)A floor, not a recommendation.
Minimum footprint70 cm longA pair holds ground around one cave; the footprint has to contain that plus somewhere the other fish can be.
Water flowlowMatch the outflow to this rather than to the filter's rating.
Lid requiredRecommendedReduces evaporation and prevents accidents.
StructureDeep leaf litter, caves, shade and tannin-stained water.

Group size and social behaviour

Forms lasting pairs and defends a cave rather than a harem territory. Two pairs need genuinely separate ends of a tank.

Structure
Pair

Behaviour

  • Works the litter layer and disappears into it when startled.
  • The female's display pattern is the conspicuous one, which reverses the usual expectation.

Telling males from females

Females carry the bold black oblique bars in breeding condition; males are larger, plainer and blue-flushed.

Feeding

Diet type
Micropredator
Staples
Frozen bloodworm and cyclops, Live blackworm, Baby brine shrimp

Breeding

Strategy
Cave spawning with the female guarding and the male holding the wider area
Difficulty
challenging
Parental care
guarding

Eggs generally fail above about pH 6, which is where most attempts in tap water end.

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.

  • Almost entirely wild-caught from the Rio Negro, and arrives needing quarantine and soft water rather than a community tank.
  • A guarding female will not tolerate corydoras near the cave, which is where mixed bottom-stocking usually goes wrong.

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
Rio Negro drainage, Brazil
Habitat
Blackwater forest streams over deep leaf litter, very soft and strongly acidic.

What the checklists say

1 distribution statement 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
Recorded as present, establishment means not stated1The source records the species as present and does not say whether it is native or introduced. AquariumHQ does not fill that in.

No checklist AquariumHQ holds positively calls this species native anywhere, so the native range above rests on AquariumHQ’s own reading of the literature rather than on a cited checklist.

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 nameNannacara adoketaObserved / measuredhigh confidenceCatalogue of Life; GBIF — Global Biodiversity Information Facility
native rangeRio Negro drainage, BrazilObserved / measuredmoderate confidenceGBIF — Global Biodiversity Information Facility
adult size6–9 cmAquarium-literature consensuslow confidenceAquariumHQ husbandry synthesis
lifespan3–5 yearsAquarium-literature consensuslow confidenceAquariumHQ husbandry synthesis
temperature24–29 °CAquarium-literature consensuslow confidenceAquariumHQ husbandry synthesis
ph4.5–6 pHAquarium-literature consensuslow confidenceAquariumHQ husbandry synthesis
general hardness0–4 °dGHAquarium-literature consensuslow 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 2026-08-13. 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 checkableLimited evidence — treat with caution.

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. 1 distribution statements held, and not one of them states an establishment means. Presence without native-or-introduced is not a native-range claim, so this stays below requirement rather than being read as one.

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.