Harrison's Pencilfish Care Guide
Nannostomus harrisoni is a slim pencilfish endemic to the Demerara basin of Guyana, with reddish fins in males and a preference for soft, acidic water.
Compiled by Aquairi from published sources · Published · Updated
Overview
Nannostomus harrisoni is a slim pencilfish of the family Lebiasinidae. Males show red pigmentation in the pelvic, anal and caudal fins, while females have hyaline pelvic and anal fins. Seriously Fish gives a maximum size of about 40-45 mm, and notes the cryptic, vertically barred pattern the fish adopts at night.
Taxonomy
- Family: Lebiasinidae
- Genus: Nannostomus
- Scientific name: Nannostomus harrisoni (Eigenmann, 1909)
Habitat
FishBase and Seriously Fish record the species as endemic to the Demerara River basin in eastern Guyana, including tributaries such as the Haiama, Kuruabaru and associated creeks. These are soft, acidic forest waters.
Tank requirements
- Minimum tank volume: 80 L
- Temperature: 22-28 °C (72-82 °F)
- pH: 5.0-7.0
- GH: 1-8 °dGH (soft, acidic water preferred)
- School size: 6 or more, ideally 10 or more
- Lifespan: 3-5 years
- Use gentle filtration and a well-planted layout
Diet
Seriously Fish describes the species as a micropredator on tiny invertebrates and zooplankton. In the aquarium it should be offered daily meals of small live and frozen foods such as Artemia nauplii, Moina and grindal worm, in addition to suitable dried preparations.
Compatibility
Nannostomus harrisoni is very peaceful but, due to its small size and timid nature, is best kept among similarly small, calm species. It is highly gregarious and should be maintained in groups of ten or more. Suitable companions include peaceful characids, small catfishes and dwarf cichlids.
Breeding
According to Seriously Fish, breeding is rarely achieved in captivity and generally requires densely planted, mature tanks or dedicated spawning setups.
Harrison's Pencilfish Breeding Guide
Overview
Nannostomus harrisoni is a slim pencilfish endemic to the Demerara River basin in eastern Guyana, including tributaries such as the Haiama and Kuruabaru rivers. Seriously Fish records a size of 40-45 mm SL. It is a peaceful, gregarious, top-dwelling species best suited to soft acidic water.
Sexing
Males display red pigmentation in the pelvic, anal and caudal fins, whereas females have hyaline (clear) pelvic and anal fins with paler caudal colouration. Males are slimmer than females, especially gravid females (Seriously Fish).
Conditioning
As a micropredator it should receive daily meals of small live and frozen fare such as Artemia nauplii, Moina and grindal worm. Soft, acidic water suits it: Seriously Fish gives 22-28 C, pH 5.0-7.0 and hardness 18-179 ppm. Keep groups of ten or more, as males rarely engage in aggression.
Breeding Setup
Seriously Fish notes that controlled breeding requires densely planted containers with fine wool mops or plants, which provide both spawning sites and refuge for the scattered eggs in the absence of parental care.
Egg & Fry Care
Reproduction has been achieved in aquaria, albeit rarely. Adults spawn after 2-3 days together and can then be removed; fry appear a day or two later (Seriously Fish). As with other Nannostomus, the smallest live and prepared foods are required for the first-feeding fry.