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No federal permit to keepOneline tetra
Nannaethiops unitaeniatus
Fishes › Tetras, piranhas and pacus (Characiformes) › Distichodontidae (Distichodus and African characins)
Care follows the distichodus and african characins guide below.
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 2.4 in / 6.2 cm).
- Water: Freshwater.
- Temperature: 73–79°F (range recorded for this species).
- pH: 6.5–7.5.
- Hardness: 0–12 dGH.
- Layout: An open-water swimmer: needs long, open swimming space with few obstacles.
- Diet: FishBase classes it as a carnivore.
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 24 × 12 in (roughly 14 US gallons); space needed is rated “modest tank”.
- Water: a fairly wide range, from slightly acidic to slightly alkaline, 72–79 °F, pH 6.5–7.5, 5–12 dGH.
- Behaviour: a shoaling fish best kept in a group of six or more.
- Difficulty: Moderate (Seriously Fish rating).
Short excerpts from the species profile:
- Setup: “Seems to do best in a well-planted set-up, preferably with subdued lighting.”
- Diet: “In nature it's something of an opportunistic omnivore, feeding on small invertebrates, algae and other zooplankton.”
- Tankmates: “A shy species that nevertheless can be maintained in a community tank with other small, peaceful species.”
- Breeding: “Not often bred in aquaria.”
From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167
Distichodus and African characins
Applies to most species in this group. Habitat: These African freshwater fishes inhabit rivers, lakes and ponds, ranging from large Distichodus to small stream-dwelling Nannaethiops (sixband, oneline). Individual species can differ, so compare with the species numbers above and the linked sources.
Housing & setup
- D. sexfasciatus: at least 240 × 90 × 60 cm, approximately 1,296 L for one; groups need substantially more space (sixband).
- Nannaethiops unitaeniatus: 60 × 30 × 30 cm, approximately 54 L for a small shoal (oneline).
- Large Distichodus: smooth rocks, wood and some water movement; most plants will be eaten (sixband).
- Fit a heavy, tight cover for jumping Distichodus (sixband).
- Nannaethiops: dense planting, floating cover and subdued lighting (oneline).
Climate & lighting
| Water | 71.6–78.8°F |
Diet
- Distichodus: Spirulina flakes, blanched spinach and shelled peas (sixband).
- Distichodus: earthworms, prawn and mussel (sixband).
- Nannaethiops: small live/frozen invertebrates and algae-based food; dried food may initially be refused (oneline).
Social life
- Adult sexfasciatus can become aggressive; Nannaethiops is shy and peaceful and needs a shoal with gentle companions (sixband, oneline).
Health watch
- Ammonia toxicity from inadequate biofiltration (fish_health).
- Parasitic skin and gill infections (fish_health).
- Nutritional deficiencies from unsuitable diets (fish_health).
Understanding the animal
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. Distinguished from Neolebias by its always complete lateral line. |
| Water it lives in | Freshwater, 73–79 °F (23–26 °C), pH 6.5–7.5, hardness 12 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, 73–79 °F.
Native climate (measured)
Native climate (measured)
| Warm-season highs | about 89°F (up to 93°F in the hottest sampled areas) |
| Cool-season lows | about 69°F (down to 64°F in the coldest sampled areas) |
| Average temperature | 75–81°F across sampled records |
| Relative humidity | 79–84% on average (driest month about 79%) |
| Rainfall | about 1652 mm a year |
Measured at 51 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.
| 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 | Distinguished from Neolebias by its always complete lateral line. Feeds on worms, crustaceans and insects. — 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.
Maximum recorded lifespan
Longest recorded lifespan reported by each database; typical lifespans are usually shorter.
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 24 × 12 in (about 14 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: Distichodus sexfasciatus Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
- Seriously Fish: Nannaethiops unitaeniatus 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.
- Merck Veterinary Manual: Management of Aquarium Fish Zoo, university or veterinaryAdded in the 2026 source-checked care-guide review.
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