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FishfreshwaterUndemanding

Javan kuhli loach

The banded eel-shaped loach almost everybody has kept and almost nobody has correctly identified. It differs from the true kuhli loach in a detail — whether the dark bands meet underneath — that is invisible unless the fish is looked at from below.

Quick profile

Scientific name
Pangio semicincta
Adult size
7–10 cm (2.8–3.9 in)
Lifespan
8–12 years
Temperature
23–28 °C (73–82 °F)
pH
5.5–7
Hardness
1–10 °dGH
Minimum tank
60 L (16 US gal)
Minimum length
60 cm
Swimming zone
Bottom
Social
Shoaling — at least 6
Diet
Omnivore
Overall confidence
moderate confidence

What keeping this species involves

Hardy and long-lived in soft warm water, provided the substrate is fine enough to burrow into and it is kept in numbers.

Slow forest streams over sand and leaf litter, shaded and tannin-stained.

Identity and names

Common name
Javan kuhli loach
Scientific name
Pangio semicincta
Family
Cobitidae
Order
Cypriniformes
Class
Actinopterygii
Also sold as
half-banded kuhli, kuhli loach, Pangio semicincta

Name ambiguity

The species most often sold as 'kuhli loach'. True Pangio kuhlii has bands that close completely around the belly; P. semicincta's bands stop part-way down the flank, which is where the name comes from.

Adult size and growth

7–10 cm (2.8–3.9 in)

Typical lifespan in an aquarium: 8–12 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 needs continuous soft substrate to burrow into and leaf litter to work through; floor area rather than depth.

RequirementValueNotes
Temperature23–28 °C (73–82 °F)Stability matters more than hitting an exact figure.
pH5.5–7A 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 volume60 L (16 US gal)A floor, not a recommendation.
Minimum footprint60 cm longA group needs continuous soft substrate to burrow into and leaf litter to work through; floor area rather than depth.
Water flowlowMatch the outflow to this rather than to the filter's rating.
Lid requiredRecommendedReduces evaporation and prevents accidents.
StructureFine sand, leaf litter and shaded cover. It burrows, and a substrate it cannot enter removes most of its behaviour.

Group size and social behaviour

Rests in tangled groups under cover and forages together after dark. Kept singly it is almost never seen.

Structure
Shoaling
Minimum group
6
Better group
10 or more

Behaviour

  • Burrows into sand and lies buried for long periods during the day.
  • Becomes active at dusk and works through leaf litter in a loose group.

Feeding

Feeds mostly after dark. Food that arrives at lights-out reaches it; food at midday does not.

Diet type
Omnivore
Staples
Sinking pellets and wafers, Frozen bloodworm and daphnia, Live blackworm

Breeding

Strategy
Egg-scattering among floating plant roots, rarely observed
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.

Risk this species poses to common tankmates
TowardsRiskWhat it means
Small fishnoneAnything that fits in the mouth is at risk once this species reaches adult size.
Adult dwarf shrimpnoneCover reduces losses but rarely prevents them where the risk is high.
ShrimpletsmoderateDetermines whether a shrimp colony can grow rather than merely persist.
SnailsnoneApplies to snails you wanted as well as snails you did not.
Long or trailing finsnoneFin 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.

  • Disappears into filter intakes. Uncovered intakes are a routine cause of loss for a fish this shape.
  • Scaleless enough to be sensitive to copper and to standard-dose ich treatment.
  • Kept alone it hides permanently, which reads as a shy fish and is an unmet social requirement.

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
Malay Peninsula, Sumatra and Borneo
Habitat
Slow forest streams over sand and leaf litter, shaded and tannin-stained.

What the checklists say

3 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 stated3The 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 namePangio semicinctaObserved / measuredhigh confidenceCatalogue of Life; GBIF — Global Biodiversity Information Facility
native rangeMalay Peninsula, Sumatra and BorneoObserved / measuredmoderate confidenceGBIF — Global Biodiversity Information Facility
adult size7–10 cmAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
lifespan8–12 yearsAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
temperature23–28 °CAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
ph5.5–7 pHAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
general hardness1–10 °dGHAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
minimum tank volume≥ 60 LAquariumHQ editorial positionmoderate confidenceAquariumHQ husbandry synthesis
minimum tank length≥ 60 cmAquariumHQ editorial positionmoderate confidenceAquariumHQ husbandry synthesis
minimum group size≥ 6AquariumHQ 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 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. 3 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.

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.