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No federal permit to keepAnduzi's Nannostomus
Nannostomus anduzei
Fishes › Tetras, piranhas and pacus (Characiformes) › Lebiasinidae (Pencilfish and splash tetras)
Nannostomus anduzei, Anduzi's pencilfish, is a species of freshwater ray-finned fish belonging to the family Lebiasinidae, the pencil fishes, splashing tetras and related fishes.
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 0.6 in / 1.6 cm).
- Water: Freshwater.
- Temperature: 75–82°F (range recorded for this species).
- Layout: Uses both the bottom and open water: give open swimming space plus cover near the substrate.
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 18 × 12 in (roughly 11 US gallons); space needed is rated “modest tank”.
- Water: soft, acidic water, 72–82 °F, pH 5–7, 1–5 dGH.
- Behaviour: temperament peaceful; a shoaling fish best kept in a group of six or more; not a community fish.
- Difficulty: Moderate (Seriously Fish rating).
Short excerpts from the species profile:
- Setup: “Should ideally be kept in a heavily-planted set-up, preferably with a dark substrate.”
- Diet: “A micropredator feeding on tiny invertebrates and other zooplankton in nature.”
- Tankmates: “Very peaceful but does not make an ideal community fish due to its small size and rather timid nature.”
- Breeding: “Has been achieved in aquaria, albeit rarely, and in a densely-planted, mature aquarium it's possible that small numbers of fry may start to appear without intervention.”
From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167
Pencilfish and splash tetras
Applies to most species in this group. Habitat: Common pencilfish and splash tetras inhabit vegetated South American streams and tributaries, with Copella also entering flooded forest. Individual species can differ, so compare with the species numbers above and the linked sources.
Housing & setup
- N. beckfordi needs a base of at least 18 × 12 inches; C. arnoldi needs at least 36 × 12 inches for long-term care.
- Use dense planting, floating plants, branches and leaf litter for shade and broken sight lines.
- Use gentle filtration for pencilfish; provide well-oxygenated water with slight surface agitation for splash tetras.
- For breeding C. arnoldi provide about 4 inches between water and cover, plus overhanging spawning surfaces.
- Use a biologically mature aquarium; splash tetras are sensitive to chemistry swings.
Climate & lighting
| Water | 69.8–80.6°F |
Diet
- Dry foods small enough for their mouths.
- Daily small live or frozen Artemia nauplii, Moina or grindal worms.
- Small gut-loaded fruit flies or crickets for C. arnoldi.
Social life
- Keep N. beckfordi in groups of 10 or more and C. arnoldi in mixed-sex groups of 8–10; choose peaceful small companions. Male pencilfish spar, so provide visual barriers.
Health watch
- Water-quality stress in immature aquaria.
- Nutritional deficiencies from unsuitable food sizes or limited diets.
- Freshwater white spot and other skin/gill parasites.
Understanding the animal
About this animal
About this animal
It is native to Venezuela and northern Brazil, particularly the upper Orinoco and Rio Ererê, a tributary of the Rio Negro. The adults grow to a maximum length of only 16 mm (0.63 in), making them one of the smallest pencilfish.
Quoted from the Wikipedia article “Nannostomus anduzei” (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. Uses both the bottom and open water. |
| Water it lives in | Freshwater, 75–82 °F (24–28 °C). |
| Climate | Tropical climate. |
What this means for care
- Keep water within its wild range, 75–82 °F.
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 | Nannostomus anduzei, Anduzi's pencilfish, is a species of freshwater ray-finned fish belonging to the family Lebiasinidae, the pencil fishes, splashing tetras and related fishes. It is native to Venezuela and northern Brazil, particularly the upper Orinoco and Rio Ererê, a tributary of the Rio Negro. The adults grow to a maximum length of only 16 mm, making them one of the smallest pencilfish. Other common names include miniature pencilfish, miniature nannostomus, and Anduzi's nannostomus. — 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 |
| Wild diet | Typically of the Lebiasinidae, N. anduzei is an omnivore, and with its small overall size and mouth takes small food items. In the wild, these likely include small invertebrates from the water column, as in an aquarium setting, where crushed flake food and dried or frozen natural food are taken. — Wikipedia (community-edited) |
| Appearance and size | This is a very small fish: even fully grown adults are only a maximum of about 16 mm, and it can become sexually mature at only 11 mm. As such, it is the smallest member of its genus currently known, the next smallest being N. minimus, which is not sexually mature until about 14 mm in length. Though small in size, the species is strikingly colored. — Wikipedia (community-edited) |
| History and naming | Nannostomus anduzei was first formally described in 1987 by the Venezuelan ichthyologist Justa M. Fernandez and the American ichthyologist Stanley Howard Weitzman, with its type locality given as Laguna Provincial, about 20 km north of Puerto Ayacucho, approximately 5°50'N, 67°30'W, in the Departmento de Ature, Amazonas, Venezuela. — 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 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.
pH
Water hardness
Minimum tank footprint
Seriously Fish recommends a tank base of at least 18 × 12 in (about 11 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.
- Nannostomus beckfordi — Seriously Fish Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
- Copella arnoldi — Seriously Fish Experienced keeper or breederAdded in the 2026 source-checked care-guide review.
- Disorders and Diseases of Fish — Merck Veterinary Manual Zoo, university or veterinaryAdded in the 2026 source-checked care-guide review.
- Parasitic Diseases of Fish — Merck Veterinary Manual 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.
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