A peaceful, slender schooling fish native to the sluggish rivers and swamps of South America. They are famous for the males' harmless but spectacular lateral sparring displays. They require heavily planted aquariums with gentle flow and make excellent tank mates for other peaceful, soft-water species. A tight-fitting lid is essential as they are known to be proficient jumpers.
At a Glance
Tank Requirements
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Water Parameters
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Temperament & Compatibility
Available Varieties
Each variety inherits the species defaults above. Only differences are highlighted.
Standard
The standard form available in the hobby. Best kept in groups of 6 or more (ideally 10+) with a mix of males and females to encourage natural sparring displays and vibrant coloration.
Differs in 1 trait from base species
Also known as: Golden Pencilfish, Wild Type
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🟢Ideal Tank MatesBeckford's Pencilfish Care Guide Summary
The Beckford's Pencilfish, scientifically known as Nannostomus beckfordi, belongs to the Characins family group. Adults reach a maximum size of approximately 6.5 cm and have a fusiform body shape with a moderate growth rate. Classified as peaceful, this species primarily occupies the surface and mid-level zones of the aquarium and produces a low level of biological waste.
To thrive, the Beckford's Pencilfish requires a freshwater only aquarium with a minimum volume of 60 litres and a tank length of at least 60 cm. Water temperature should be maintained between 22°C and 28°C, with a pH range of 5–7.5 and a general hardness of 1–15 dGH. A low water flow is preferred. An aquarium test kit can help you monitor these values.
Due to its specialist needs, the Beckford's Pencilfish is best suited for fishkeepers who can provide a carefully planned setup. The Beckford's Pencilfish is typically available in one standard form.
Beckford's Pencilfish Habitat Setup
When setting up an aquarium for the Beckford's Pencilfish, a low water flow best suits their natural preferences. Because this species occupies the surface and mid-level zones, the aquarium layout should prioritise adequate surface area with floating cover to make them feel secure near the waterline and open swimming space in the centre of the tank for free movement. Useful additions include leaf litter or blackwater tannins to replicate their natural soft-water habitat, dense planting to provide cover, break sightlines, and reduce stress, and floating plants to diffuse overhead light and create shaded areas. Keepers should note that a tight-fitting lid is essential, as this species is a known jumper.
Beckford's Pencilfish Compatibility Notes
Classified as peaceful, the Beckford's Pencilfish is a schooling species that feels most secure in a sizeable group, where natural shoaling behaviour reduces stress and brings out their best colours. Selecting tankmates that favour different water layers from the surface and mid-level zones can help reduce competition and territorial overlap.
Recommended Tank Sizes
Standard aquarium sizes that meet the minimum volume and length requirements for Beckford's Pencilfish.
20 Gallon High
20 Gallon Long
29 Gallon Standard
30 Gallon Breeder
36 Gallon Bowfront
40 Gallon Breeder
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Frequently Asked Questions About Beckford's Pencilfish
How big does Beckford's Pencilfish get?
Beckford's Pencilfish (Nannostomus beckfordi) typically reaches a maximum adult size of approximately 6.5 cm. They have a fusiform body shape and a moderate growth rate.
What tank size does Beckford's Pencilfish need?
A minimum aquarium volume of 60 litres and a tank length of at least 60 cm are recommended for Beckford's Pencilfish. This ensures enough swimming space and helps maintain stable water conditions.
What water parameters does Beckford's Pencilfish need?
Beckford's Pencilfish thrives in freshwater only conditions with a temperature range of 22–28°C, a pH between 5 and 7.5, and a general hardness of 1–15 dGH. A low water flow is preferred.
Is Beckford's Pencilfish peaceful or aggressive?
Beckford's Pencilfish is classified as peaceful with an aggression score of 2 out of 10. They are generally well-suited to peaceful community tanks.
How many Beckford's Pencilfish should be kept together?
Beckford's Pencilfish is a schooling species and should be kept in groups of at least 6. Larger groups help distribute aggression and encourage natural schooling behaviour.
Does Beckford's Pencilfish have any special tank requirements?
Yes. Beckford's Pencilfish benefits from plants - densely covered, plants - floating, and leaf litter/blackwater in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.
Does Beckford's Pencilfish need a lid on the tank?
Yes. Beckford's Pencilfish is a known jumper, and a tight-fitting lid or cover is essential to prevent escape. Even a small gap can be enough for a determined fish to leap out.
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