Kuhli loach
An eel-shaped, burrowing loach that spends daylight hidden and emerges after dark. Sold as a single 'algae eater' and needing neither of those things — it is a social bottom-dweller that eats food, not algae.
Quick profile
- Scientific name
- Pangio kuhlii
- Adult size
- 8–10 cm (3.1–3.9 in)
- Lifespan
- 7–10 years
- Temperature
- 24–29 °C (75–84 °F)
- pH
- 5–7.5
- Hardness
- 1–10 °dGH
- Minimum tank
- 75 L (20 US gal)
- Minimum length
- 60 cm
- Swimming zone
- Bottom
- Social
- Shoaling — at least 6
- Diet
- Detritivore
- Overall confidence
- moderate confidence
What keeping this species involves
Undemanding once settled, but needs soft substrate, real cover and a group. Also escapes through filter intakes and unsealed gaps.
Soft, shaded forest streams with sand and thick leaf litter.
Identity and names
- Common name
- Kuhli loach
- Scientific name
- Pangio kuhlii
- Family
- Cobitidae
- Order
- Cypriniformes
- Class
- Actinopterygii
- Also sold as
- coolie loach, leopard loach
Name ambiguity
Several Pangio species are sold as 'kuhli loach', including P. kuhlii, P. semicincta and P. myersi. The banded fish most commonly in trade is often P. semicincta rather than true P. kuhlii. Husbandry is similar across the group.
Adult size and growth
8–10 cm (3.1–3.9 in)
Typical lifespan in an aquarium: 7–10 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
Floor area matters far more than water volume; a wide 60 cm tank with soft sand gives the group somewhere to burrow.
| Requirement | Value | Notes |
|---|---|---|
| Temperature | 24–29 °C (75–84 °F) | Stability matters more than hitting an exact figure. |
| pH | 5–7.5 | A stable pH outside the ideal band is usually better than an unstable one inside it. |
| General hardness | 1–10 °dGH | Check your supplier's published figure before choosing species. |
| Minimum volume | 75 L (20 US gal) | A floor, not a recommendation. |
| Minimum footprint | 60 cm long | Floor area matters far more than water volume; a wide 60 cm tank with soft sand gives the group somewhere to burrow. |
| Water flow | moderate | Match the outflow to this rather than to the filter's rating. |
| Lid required | Recommended | Reduces evaporation and prevents accidents. |
| Structure | Soft sand, leaf litter and multiple caves. Sharp gravel damages the skin and barbels. |
Behaviour
- Burrows into sand and disappears for days at a time — normal, not a sign of a problem.
- Squeezes into any gap, including filter intakes and the space behind background panels.
Feeding
Not an algae eater. Feed sinking food after lights-out until the group settles.
- Diet type
- Detritivore
- Staples
- Sinking dry foods, Frozen bloodworm, Frozen daphnia
Breeding
- Strategy
- Egg-scattering; rarely spawns in aquaria
- Difficulty
- rarely achieved
- Parental care
- none
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 | moderate | 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 | 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.
- Gravel substrate is a genuine welfare problem for this species, not a preference.
- Scaleless and unusually sensitive to copper-based and formalin medications; dose at reduced rates or not at all.
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
- Sumatra, Java, Borneo and the Malay Peninsula
- Habitat
- Soft, shaded forest streams with sand and thick leaf litter.
What the checklists say
6 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 | 3 | 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 | Pangio kuhlii | Observed / measured | high confidence | Catalogue of Life; GBIF — Global Biodiversity Information Facility |
| native range | Sumatra, Java, Borneo and the Malay Peninsula | Observed / measured | moderate confidence | GBIF — Global Biodiversity Information Facility |
| adult size | 8–10 cm | Aquarium-literature consensus | moderate confidence | AquariumHQ husbandry synthesis |
| lifespan | 7–10 years | Aquarium-literature consensus | moderate confidence | AquariumHQ husbandry synthesis |
| temperature | 24–29 °C | Aquarium-literature consensus | moderate confidence | AquariumHQ husbandry synthesis |
| ph | 5–7.5 pH | Aquarium-literature consensus | moderate confidence | AquariumHQ husbandry synthesis |
| general hardness | 1–10 °dGH | Aquarium-literature consensus | moderate confidence | AquariumHQ husbandry synthesis |
| minimum tank volume | ≥ 75 L | AquariumHQ editorial position | moderate confidence | AquariumHQ husbandry synthesis |
| minimum tank length | ≥ 60 cm | AquariumHQ editorial position | moderate confidence | AquariumHQ husbandry synthesis |
| minimum group size | ≥ 6 | 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 fishbase 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. 6 distribution statements held from GBIF checklists — introduced in 3 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 sizeOne sourceBased on a verified authoritative source.1 citation, 1 independent origin
A single source: fishbase.
- 12 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.
temperatureIndependently verifiedConfirmed by more than one independent source.2 citations, 2 independent origins
2 citations from 2 independent origins.
- 22–27 °C — Ornamental Aquatic Trade Association · Recommended for keeping · Recommended for keeping · checked 2026-08-11
- 24–30 °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. 2 independent origins.
What would improve this: Nothing. Recheck when the sources are next reviewed.
phOne sourceAquariumHQ's own position, derived from evidenced inputs.1 citation, 1 independent origin
A single source: fishbase.
- 5.5–6.5 pH — 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 pH 5.0–7.5; FishBase records 5.5–6.5. The recorded range is one pH unit wide, which for a fish distributed across Sumatra, Java and Borneo is a locality reading rather than a species envelope. Kuhli loaches are kept successfully across a much wider pH span than that, and advising only 5.5–6.5 would exclude most of the water they actually live in. The acid end is the well-supported part and both figures agree on it.
What would improve this: Corroborate against a second, independent source.
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.
No more than 5 dGH — the source does not state a lower boundFishBase gives the dH range as "? - 5". The upper bound is published and the lower is not. Recording a floor of zero would look identical to a measured one, so the finding is kept as a constraint: no harder than 5 dGH.
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.
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.
Group size and social behaviour
Kept singly or in pairs they hide permanently. In a group of six or more they emerge and forage together, often in daylight.