Cardinal Sulawesi shrimp
The dwarf shrimp that inverts every rule the others taught: it needs warm, hard, alkaline water, and the soft acidic conditions that suit Caridina and Neocaridina everywhere else will kill it. It is endemic to one lake, which is under real pressure.
Quick profile
- Scientific name
- Caridina dennerli
- Adult size
- 1.5–2 cm (0.6–0.8 in)
- Lifespan
- 1–2 years
- Temperature
- 27–30 °C (81–86 °F)
- pH
- 7.5–8.5
- Hardness
- 4–8 °dGH
- Minimum tank
- 20 L (5 US gal)
- Minimum length
- 30 cm
- Swimming zone
- Bottom
- Social
- Colony — at least 10
- Diet
- Detritivore
- Overall confidence
- low confidence
What keeping this species involves
Wants warm hard alkaline water held very stable, an established biofilm, and no tankmates. It is the least forgiving dwarf shrimp in general trade.
Rocky shoreline of an ancient tectonic lake — warm, hard, alkaline and very stable.
Identity and names
- Common name
- Cardinal Sulawesi shrimp
- Scientific name
- Caridina dennerli
- Family
- Atyidae
- Order
- Decapoda
- Class
- Malacostraca
- Also sold as
- cardinal shrimp, white-spot cardinal, Caridina dennerli
Adult size and growth
1.5–2 cm (0.6–0.8 in)
Typical lifespan in an aquarium: 1–2 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: elongate with a grazing or sucking mouth. Assigned from what is typical of Atyidae, not examined for this species.
Water and tank requirements
A colony grazes rock surfaces; the requirement is stable heated water over structured hardscape rather than swimming room.
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
Sulawesi ancient lake — Lake Matano, one of the Malili lakes
The Malili lakes and Lake Poso — ancient, isolated, clear tectonic lakes on ultramafic rock in central Sulawesi, holding an endemic fauna found nowhere else.
Alkaline and warm and NOT hard, which is the combination the hobby finds hardest to produce and the one these animals actually need. Adding a rift-lake salt mix overshoots the hardness badly while getting the pH about right.
- Conductivity
- 140–260 µS/cm
- Flow
- low
- Dissolved oxygen
- near saturation
- Seasonality
- weak
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 — Lake Matano, one of the Malili lakes. Sulawesi ancient lake generally runs 27–31°C, and the advised band of 27–30°C is consistent with it. This is AquariumHQ's reasoning from the habitat, not a measurement of the species.
- pHFollows the habitat this animal comes from
- Follows the water this animal is recorded from — Lake Matano, one of the Malili lakes. Sulawesi ancient lake generally runs 7.5–8.6, and the advised band of 7.5–8.5 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 — Lake Matano, one of the Malili lakes. Sulawesi ancient lake generally runs 3–9 dGH, and the advised band of 4–8 dGH is consistent with it. This is AquariumHQ's reasoning from the habitat, not a measurement of the species.
Scale: 26.4 to 31.6 °C.
Scale: 7.3 to 8.8 pH.
Scale: 2.1 to 9.9 dGH.
| Requirement | Value | Notes |
|---|---|---|
| Temperature | 27–30 °C (81–86 °F) | Stability matters more than hitting an exact figure. |
| pH | 7.5–8.5 | A stable pH outside the ideal band is usually better than an unstable one inside it. |
| General hardness | 4–8 °dGH | Check your supplier's published figure before choosing species. |
| Carbonate hardness | 2–6 °dKH | Buffering capacity — what stops the pH moving. |
| Minimum volume | 20 L (5 US gal) | A floor, not a recommendation. |
| Minimum footprint | 30 cm long | A colony grazes rock surfaces; the requirement is stable heated water over structured hardscape rather than swimming room. |
| Water flow | low | Match the outflow to this rather than to the filter's rating. |
| Lid required | Recommended | Reduces evaporation and prevents accidents. |
| Structure | Rock and mature biofilm, with very stable temperature and chemistry. This species reacts badly to change of any kind. |
Behaviour
- Grazes rock surfaces and gathers in groups on food.
- Waves the front limbs continuously while feeding.
Feeding
Grazes films from hard surfaces. A tank without an established biofilm cannot support it, however well it is fed.
- Diet type
- Detritivore
- Staples
- Biofilm on rock, Powdered shrimp foods, Blanched vegetables
Breeding
- Strategy
- Direct development — females carry a small number of large eggs
- Difficulty
- challenging
- Parental care
- carries eggs
Broods are small, in the order of a dozen, so a colony grows slowly even when everything is right.
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 | none | Anything that fits in the mouth is at risk once this species reaches adult size. |
| Adult dwarf shrimp | none | Cover reduces losses but rarely prevents them where the risk is high. |
| Shrimplets | none | Determines whether a shrimp colony can grow rather than merely persist. |
| Snails | none | Applies to snails you wanted as well as snails you did not. |
| Long or trailing fins | none | Fin damage is an entry point for secondary infection. |
| Plants | grazes-algae | 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.
- Kept in the soft acidic water that suits crystal red shrimp it dies, and the failure is often blamed on fragility rather than on chemistry.
- Endemic to Lake Matano. Wild collection has been substantial and the lake is affected by mining and introduced fish; captive-bred stock is the responsible source where it can be found.
- Intolerant of temperature swings. An unheated room in winter is enough to end a colony.
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 Matano, Sulawesi, Indonesia — endemic to a single lake
- Habitat
- Rocky shoreline of an ancient tectonic lake — warm, hard, alkaline and very stable.
What the checklists say
4 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 |
|---|---|---|
| Introduced | 1 | 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 | 3 | The 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.
| Claim | Value | Evidence type | Confidence | Source |
|---|---|---|---|---|
| scientific name | Caridina dennerli | Observed / measured | high confidence | Catalogue of Life; GBIF — Global Biodiversity Information Facility |
| native range | Lake Matano, Sulawesi, Indonesia — endemic to a single lake | Observed / measured | moderate confidence | GBIF — Global Biodiversity Information Facility |
| adult size | 1.5–2 cm | Aquarium-literature consensus | low confidence | AquariumHQ husbandry synthesis |
| lifespan | 1–2 years | Aquarium-literature consensus | low confidence | AquariumHQ husbandry synthesis |
| temperature | 27–30 °C | Aquarium-literature consensus | low confidence | AquariumHQ husbandry synthesis |
| ph | 7.5–8.5 pH | Aquarium-literature consensus | low confidence | AquariumHQ husbandry synthesis |
| general hardness | 4–8 °dGH | Aquarium-literature consensus | low confidence | AquariumHQ husbandry synthesis |
| minimum tank volume | ≥ 20 L | AquariumHQ editorial position | moderate confidence | AquariumHQ husbandry synthesis |
| minimum tank length | ≥ 30 cm | AquariumHQ editorial position | moderate confidence | AquariumHQ husbandry synthesis |
| carbonate hardness | 2–6 °dKH | Aquarium-literature consensus | low confidence | AquariumHQ husbandry synthesis |
| minimum group size | ≥ 10 | AquariumHQ editorial position | low 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 2026-08-12. 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. 4 distribution statements held from GBIF checklists — introduced in 1 country. 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.
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.
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.
- Schooling and shoalingThis species is recorded as colony, and the number it is kept in decides how it behaves.
- The kinds of water aquarium fish come fromThis record's water bands follow sulawesi ancient lake, which is the kind of water this animal is recorded from.
Group size and social behaviour
A colony animal that is slow to establish. Losses in the first weeks are usual and are mostly acclimatisation rather than husbandry.