Three-lined Pencilfish care guide
Three-lined Pencilfish (Nannostomus trifasciatus) — minimum tank 60 L, temperature 23-28 °C, pH 5-7.
Compiled by Aquairi from published sources · Published · Updated
Overview
The Three-lined Pencilfish (Nannostomus trifasciatus) is a small lebiasinid from the Amazon and upper Negro basins. The species shows three bold black horizontal stripes along a slender body, accented with red and gold blotches; at night it switches to a different vertical-bar pattern.
Taxonomy
- Family: Lebiasinidae
- Genus: Nannostomus
- Scientific name: Nannostomus trifasciatus
- Common synonyms: Three-stripe Pencilfish
Habitat
Native to soft, very acidic blackwater tributaries of the upper Amazon and Rio Negro in Brazil, Peru and Colombia, in slow-moving streams with leaf litter and shaded vegetation.
Tank requirements
- Minimum tank volume: 60 L (15.9 US gal)
- Adult size: 3-4 cm
- Temperature: 23-28 °C (73-82 °F)
- pH: 5-7
- GH: 1-8 °dGH
- Water flow: low
- Lifespan: 3-5 years
- School size: ≥6 individuals
Diet
A micro-predator and omnivore. Offer micro-pellets, finely crushed flakes and small live or frozen foods such as cyclops, daphnia and baby brine shrimp.
Compatibility
A peaceful mid-water shoaling species. Keep a group of at least six in a planted blackwater aquarium with subdued lighting. Compatible with other small characins, dwarf cichlids and freshwater shrimp.
Breeding
An egg-scatterer that spawns among fine-leaved plants in very soft, acidic water. Eggs and adults must be separated quickly, as parents readily consume eggs.
Three-lined Pencilfish Breeding Guide
Overview
The three-lined pencilfish, Nannostomus trifasciatus, is an egg-scattering free spawner exhibiting no parental care. It will spawn frequently in mature aquaria with minimal intervention, though a dedicated setup gives more dependable results.
Sexing
Adult males are more intensely coloured, especially when in spawning condition, while females are noticeably rounder-bodied.
Conditioning
Condition the adults together, then move a single pair, or a group of one or two males with several females, into the breeding container. Keeping the breeding group small helps reduce egg predation.
Breeding Setup
Use a dimly lit tank with mature water. Cover the base with mesh, plastic grass matting or glass marbles so the eggs can fall out of reach, or fill much of the tank with a fine-leaved plant such as Taxiphyllum or spawning mops. An air-powered sponge filter provides oxygenation. Slightly acidic to neutral water with a temperature towards the upper end of the 22-28 degrees C range suits spawning.
Spawning Behavior & Trigger
The fish scatter eggs freely over the medium, with eggs settling through the mesh or among the fine plants. The more individuals involved, the greater the risk of egg predation, so the breeding group is kept small.
Egg & Fry Care
Remove the adults after two to three days; the first fry should be visible around three days later. Start them on Paramecium or a proprietary dry food of 5-50 micron grade, progressing to Artemia nauplii and microworm once they are large enough.
Common Challenges
This species is more aggressive than most of its relatives, with territorial males, so spacious breeding quarters with visual barriers help, and groups of ten or more spread aggression. As with all pencilfishes, the tiny fry depend on densely available micro-foods at first.