Home / Fishes / Carp, barbs, minnows, loaches / Cyprinidae / Arulius barb
No federal permit to keepArulius barb
Dawkinsia arulius
Fishes › Carp, barbs, minnows, loaches (Cypriniformes) › Cyprinidae (Carps and barbs)
The Arulius barb (Dawkinsia arulius) is a tropical cyprinid fish native to the Kaveri River basin of south east India.
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 4.7 in / 12 cm).
- Water: Freshwater.
- Temperature: 66–77°F (range recorded for this species).
- pH: 6–6.5.
- Hardness: 0–10 dGH.
- Layout: Uses both the bottom and open water: give open swimming space plus cover near the substrate.
- Diet: FishBase classes it as a omnivore.
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 47 × 18 in (roughly 64 US gallons); space needed is rated “large tank”.
- Water: a fairly wide range, from slightly acidic to slightly alkaline, 66–77 °F, pH 6–7.5, 2–10 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: “Not difficult to keep in a well-maintained set-up, though we recommend aquascaping the tank to resemble a flowing stream or river with a substrate of variably-sized, water-worn rocks, sand, fine gravel and perhaps some small boulders.”
- Diet: “Probably a foraging omnivore feeding on a variety of worms, insects, crustaceans, plant material, and other organic debris in nature.”
- Tankmates: “An ideal addition to a peaceful community of riverine species alongside other schooling or shoaling cyprinids, plus botiid, cobitid, nemacheilid, and balitorid loaches.”
- Breeding: “Like most small cyprinids this is an egg-scattering free spawner exhibiting no parental care.”
From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167
Carps and barbs
Applies to most species in this group. Habitat: The listed barbs and freshwater sharks occupy Asian streams, rivers and floodplain waters, with bala sharks also using natural lakes. Individual species can differ, so compare with the species numbers above and the linked sources.
Housing & setup
- Tiger barbs need a base at least 80 × 30 cm (about 31 × 12 inches), with vegetation and driftwood cover.
- Adult bala shark groups need a base at least 240 × 60 cm (about 96 × 24 inches), ample open swimming space and a heavy, tight lid.
- Red-tailed black sharks need a base at least 120 × 45 cm (about 48 × 18 inches), with rocky refuges.
- Use efficient filtration, water movement and high oxygenation for riverine bala and red-tailed sharks.
Climate & lighting
| Water | 68–78.8°F |
Diet
- Quality flakes or granules containing plant material.
- Live or frozen Daphnia, Artemia and bloodworms.
- For larger bala sharks: chopped earthworms, prawns or mussels.
- For bala sharks: shelled peas, blanched courgette or spinach.
Social life
- Keep tiger barbs in at least 8–10 and bala sharks in at least five. Avoid timid or long-finned companions for tiger barbs. Red-tailed black sharks become territorial toward similar-looking fishes.
Health watch
- Ammonia toxicity.
- Nutritional deficiencies.
Understanding the animal
About this animal
About this animal
Other common names include Tamiraparani barb, Silas barb and longfin barb.
Quoted from the Wikipedia article “Arulius barb” (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. Uses both the bottom and open water. Inhabits large streams, rivers and lakes. |
| Water it lives in | Freshwater, 66–77 °F (19–25 °C), pH 6–6.5, hardness 10 dH. |
| Climate | Tropical climate. |
| Behavior to plan for | Breeding: open water/substratum egg scatterers. |
What this means for care
- Keep water within its wild range, 66–77 °F.
Native climate (measured)
Native climate (measured)
| Warm-season highs | about 95°F (up to 102°F in the hottest sampled areas) |
| Cool-season lows | about 62°F (down to 50°F in the coldest sampled areas) |
| Average temperature | 71–83°F across sampled records |
| Relative humidity | 62–70% on average (driest month about 53%) |
| Rainfall | about 689 mm a year, with strong wet and dry seasons |
Measured at 5 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 | The Arulius barb (Dawkinsia arulius) is a tropical cyprinid fish native to the Kaveri River basin of south east India. Other common names include Tamiraparani barb, Silas barb and longfin barb. — 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 |
| Reproduction | Spawns preferably near the surface. — FishBase |
| Appearance and size | Adult fish are dark brownish olive on the back, becoming lighter on the sides to white on the ventral surface. It has a black, vertical blotch in the middle of its body, above the origin of its pelvic fin. It has a second black, vertical blotch above its anal fin, and a third black bar or blotch on the base of the caudal fin, though less well defined as the other two blotches. — Wikipedia (community-edited) |
| Biology | Inhabits large streams, rivers and lakes. Omnivorous, peaceful and schooling. — FishBase |
| History and naming | The name arulius is derived from the name "aruli" used by local inhabitants. — Wikipedia (community-edited) |
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 total length. Fish in home aquariums often stay smaller than wild records.
Water temperature
Range the species tolerates in nature; aim for the middle.
Water hardness
Minimum tank footprint
Seriously Fish recommends a tank base of at least 47 × 18 in (about 64 US gallons).
Veterinary & husbandry research
Veterinary & husbandry research
- Outbreak of Parasitic Dinoflagellate Piscinoodinium sp. Infection in an Endangered Fish from India: Arulius Barb (Dawkinsia arulius) Sudhagar A et al., Pathogens (Basel, Switzerland) 2022
Peer-reviewed papers that mention this species alongside captivity, zoos, veterinary care or aquaculture. Some cover several species or mention it only in passing, so check the abstract. 170
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 — Puntigrus tetrazona Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
- Seriously Fish — Balantiocheilos melanopterus Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
- Seriously Fish — Epalzeorhynchos bicolor Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
- Merck Veterinary Manual — Disorders and Diseases of Fish Zoo, university or veterinaryAdded 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.
- PubMed (U.S. National Library of Medicine) Peer-reviewed researchIndex of peer-reviewed veterinary, zoo and husbandry research.
- iNaturalist (captive observations) Community referenceCommunity observation platform run by the California Academy of Sciences and National Geographic; observations marked captive show animals living in homes, zoos and aquariums.
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