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No federal permit to keepBlack-lined loach
Ambastaia nigrolineata
Fishes › Carp, barbs, minnows, loaches (Cypriniformes) › Botiidae (Clown, yoyo and other loaches)
Ambastaia nigrolineata is a vulnerable species of loach found in the Mekong basin in Southeast Asia and China.
Care at a glance
Species-specific aquarium care
- Tank: At least 24 in long and 12 in front to back for one adult (adults commonly reach about 3.1 in / 8 cm).
- Water: Freshwater.
- Temperature: 59–77°F (range recorded for this species).
- pH: 7–7.5.
- Hardness: 5–15 dGH.
- Layout: Lives on or near the bottom: floor space and hiding places matter more than height.
- Diet: FishBase classes it as a carnivore.
- Availability: Rarely or never seen in the aquarium trade; expect to source it from specialists or not at all.
Calculated from this species' own FishBase record: tank size from its typical adult length and swimming zone, water values from its recorded ranges. The group guide below fills in general care.
Care guide
Species care notes
- Tank: a base of at least 35 × 12 in (roughly 21 US gallons); space needed is rated “large tank”.
- Water: a fairly wide range, from slightly acidic to slightly alkaline, 68–77 °F, pH 6.5–7.5, 5–15 dGH.
- Behaviour: a shoaling fish best kept in a group of six or more; suited to a community tank.
- Difficulty: Moderate (Seriously Fish rating).
Short excerpts from the species profile:
- Setup: “All botiids need a well-structured set-up although the actual choice of décor is more-or-less down to personal taste.”
- Tankmates: “This species is quite mild in temperament and can make an excellent community addition.”
From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167
Clown, yoyo and other loaches
Applies to most species in this group. Habitat: Botiids inhabit Asian freshwater rivers and tributaries, including forested headwaters and seasonally flooded river margins. Individual species can differ, so compare with the species numbers above and the linked sources.
Housing & setup
- Provide at least an 80 × 30 cm (31 × 12 in) base for dwarf chain loaches; clown loaches require at least 180 × 60 cm (71 × 24 in).
- Use sand or fine gravel, smooth rocks, roots and numerous shelters; fill trapping holes and remove sharp edges.
- Fit a tight lid.
- Use a mature biological filter and maintain well-oxygenated water with some flow.
- Perform routine weekly water changes of 30–50% for the dwarf chain loach setup.
Climate & lighting
| Water | 75.2–86°F |
Diet
- Quality sinking dried foods
- Live or frozen bloodworms
- Daphnia or Artemia
- Blanched spinach or courgette
Social life
- For clown and dwarf chain loaches, keep at least 5–6 conspecifics, preferably 10 or more; pairs and trios can suffer severe dominance stress. Avoid slow, long-finned tankmates.
Handling
- Take care with the erectable subocular spines when moving loaches; they can become entangled in nets.
Health watch
- Stress and failure to feed in undersized social groups
- Entrapment injuries in narrow décor
- Water-quality illness from accumulated organic waste
Understanding the animal
About this animal
About this animal
It occurs in clear, fast-flowing riffles and hillstreams with moderate currents and substrates composed primarily of sand. It is known to feed on insect larvae and other benthic organisms.
Quoted from the Wikipedia article “Ambastaia nigrolineata” (CC BY-SA 4.0) 174
In the wild
In the wild
From this species’ own FishBase record (habitat, bottom type, water and breeding data), not its family. Good care copies these conditions.1
| Where it lives | Lives in freshwater, in rivers and streams. Stays near the bottom. Occurs in riffles, in clear, fast-flowing water. |
| Water it lives in | Freshwater, 59–77 °F (15–25 °C), pH 7–7.5, hardness 5–15 dH. |
| Climate | Subtropical climate. |
What this means for care
- Keep water within its wild range, 59–77 °F.
Native climate (measured)
Native climate (measured)
| Warm-season highs | about 88°F (up to 92°F in the hottest sampled areas) |
| Cool-season lows | about 62°F (down to 47°F in the coldest sampled areas) |
| Average temperature | 69–80°F across sampled records |
| Relative humidity | 73–74% on average (driest month about 63%) |
| Rainfall | about 1790 mm a year, with strong wet and dry seasons |
Measured at 6 wild occurrence records sampled against WorldClim 2.1 climate data (1970–2000 averages). Air conditions in the range are ecological context, not enclosure settings: microhabitats such as burrows, leaf litter or basking rocks can be cooler, warmer or more humid.
From the sources
From the sources
Quoted from the matching sections of reputable sources for this exact species. Specialist databases are used first; Wikipedia (community-edited, CC BY-SA 4.0) only fills gaps. Other sources are short credited quotes.
| Overview | Ambastaia nigrolineata is a vulnerable species of loach found in the Mekong basin in Southeast Asia and China. It occurs in clear, fast-flowing riffles and hillstreams with moderate currents and substrates composed primarily of sand. It is known to feed on insect larvae and other benthic organisms. Ambastaia nigrolineata reaches 8 cm (3.1 inches) in standard length. — Wikipedia (community-edited) |
| Where it lives | Home ranges Population dynamics Growth parameters Max. ages / sizes Length-weight rel. Length-frequencies Mass conversion Recruitment Abundance Life cycle Reproduction Maturity Maturity/Gills rel. — FishBase |
| Biology | Occurs in riffles, in clear, fast-flowing water. Found in small creek with sandy bottom and moderate current and hill streams. Feeds on insect larvae and benthic organisms. — FishBase |
Data and studies
The numbers
The numbers
Each bar is what one source reports. Where several sources weigh in, the dashed gold band marks their average.
Adult length
Maximum recorded length. Measured as standard length (snout to the base of the tail, not counting the tail fin). Fish in home aquariums often stay smaller than wild records.
Water temperature
Range the species tolerates in nature; aim for the middle.
Minimum tank footprint
Seriously Fish recommends a tank base of at least 35 × 12 in (about 21 US gallons).
Sources for this sheet
- FishBase (Froese & Pauly, eds.), version 24.07 Peer-reviewed researchThe global scientific database on fishes, maintained by a consortium of research institutions; every value is referenced.
- Seriously Fish species profiles Experienced keeper or breederLong-running aquarium reference written and peer-checked by experienced fishkeepers and ichthyologists; each profile covers habitat, tank size, water, diet, behaviour and breeding.
- Seriously Fish: Chromobotia macracanthus Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
- Seriously Fish: Ambastaia sidthimunki Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
- Wikipedia (species article) Community referenceFree encyclopedia; useful overviews with their own citations. Intro text is quoted under CC BY-SA 4.0.
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