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FishfreshwaterModerate

Rusty cichlid

The mbuna usually recommended to somebody who wants a Malawi tank and has read what the others are like. It is genuinely among the least aggressive of the group, and its rusty-lavender colouring is subtle enough that it rarely triggers rivalry in blue-barred tankmates.

Quick profile

Scientific name
Iodotropheus sprengerae
Adult size
9–11 cm (3.5–4.3 in)
Lifespan
6–10 years
Temperature
24–28 °C (75–82 °F)
pH
7.6–8.8
Hardness
10–25 °dGH
Minimum tank
180 L (48 US gal)
Minimum length
100 cm
Swimming zone
All levels
Social
Harem
Diet
Omnivore
Overall confidence
moderate confidence

What keeping this species involves

Hardy in hard alkaline water and much easier to house than most mbuna. It is still a Rift Lake cichlid and still needs the chemistry.

Rocky and intermediate shoreline zones.

Identity and names

Common name
Rusty cichlid
Scientific name
Iodotropheus sprengerae
Family
Cichlidae
Order
Cichliformes
Class
Actinopterygii
Also sold as
lavender mbuna, Iodotropheus sprengerae

Adult size and growth

9–11 cm (3.5–4.3 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.

Water and tank requirements

A group with rock structure to divide the space; less territorial than most mbuna but still a fish that holds ground.

RequirementValueNotes
Temperature24–28 °C (75–82 °F)Stability matters more than hitting an exact figure.
pH7.6–8.8A stable pH outside the ideal band is usually better than an unstable one inside it.
General hardness10–25 °dGHCheck your supplier's published figure before choosing species.
Carbonate hardness8–18 °dKHBuffering capacity — what stops the pH moving.
Minimum volume180 L (48 US gal)A floor, not a recommendation.
Minimum footprint100 cm longA group with rock structure to divide the space; less territorial than most mbuna but still a fish that holds ground.
Water flowmoderateMatch the outflow to this rather than to the filter's rating.
Lid requiredRecommendedReduces evaporation and prevents accidents.
StructureRockwork with caves and open swimming water between it.

Group size and social behaviour

Mild for an mbuna. Males display more than they pursue, and mixed-sex groups settle readily.

Structure
Harem
Sex ratio
One male to two or more females.

Behaviour

  • Grazes rock and open substrate through the day.
  • Displays with fins spread rather than chasing.

Telling males from females

Males develop more egg spots and slightly stronger colour. The sexes are otherwise close.

Feeding

More omnivorous than the strict aufwuchs grazers, and correspondingly more forgiving of diet.

Diet type
Omnivore
Staples
Vegetable-based dry foods, Spirulina, Frozen brine shrimp

Breeding

Strategy
Maternal mouthbrooding
Difficulty
incidental
Parental care
mouthbrooding

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 fishmoderateAnything that fits in the mouth is at risk once this species reaches adult size.
Adult dwarf shrimpnear-certainCover reduces losses but rarely prevents them where the risk is high.
Shrimpletsnear-certainDetermines 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.
PlantsnibblesTough 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.

  • Its mildness is relative to other mbuna. It is not a community fish for soft-water species.
  • Needs hard alkaline water; kept soft and acidic it is outside its requirements whatever the first year suggests.

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
Lake Malawi — Boadzulu and Chinyankwazi Islands
Habitat
Rocky and intermediate shoreline zones.

What the checklists say

2 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
Recorded as present, establishment means not stated2The 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 nameIodotropheus sprengeraeObserved / measuredhigh confidenceCatalogue of Life; GBIF — Global Biodiversity Information Facility
native rangeLake Malawi — Boadzulu and Chinyankwazi IslandsObserved / measuredmoderate confidenceGBIF — Global Biodiversity Information Facility
adult size9–11 cmAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
lifespan6–10 yearsAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
temperature24–28 °CAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
ph7.6–8.8 pHAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
general hardness10–25 °dGHAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
minimum tank volume≥ 180 LAquariumHQ editorial positionmoderate confidenceAquariumHQ husbandry synthesis
minimum tank length≥ 100 cmAquariumHQ editorial positionmoderate confidenceAquariumHQ husbandry synthesis
carbonate hardness8–18 °dKHAquarium-literature consensusmoderate 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 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. 2 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.

carbonate 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.