Not furry, but we like them anyway.
Golden Pencilfish
Nannostomus beckfordi
Also called Beckford's pencilfish, Brown pencilfish
From South America: rivers of Guyana, Suriname and French Guiana, the lower and middle Amazon up to the lower Rio Negro, the Rio Madeira and the Orinoco in Venezuela12
At a glance the quick version
Looks how to spot one
Slender, pencil-shaped scaled characin
A slim, cigar-shaped fish with a small mouth. A dark band runs along the side, with a warm reddish to golden band above it and a darker band below, and the tail and lower fins carry red. At night it switches to a pale pattern with vertical bars. Males are brighter and have a curved rear edge to the anal fin, while females are fuller-bodied.13
Personality what they are like
A relatively peaceful fish that suits a calm community of similar-sized tetras and small catfish. Males like to spar with each other in a harmless, showy way when several are kept.12
Daily activity how busy a day looks
A steady, unhurried swimmer that patrols the middle and upper water among plants.12
Grooming and care the hands-on bits
Adaptable compared with its relatives. Suggested ranges: about 21-27 C (FishBase gives 24-26 C), pH 5.0-8.0, hardness 1-15 dGH (FishBase gives 5-19 dH). Regular partial water changes keep it at its best.12
Home where they are happiest
Tank of at least 45-60 cm length (around 41 litres or more) with dense planting, wood and leaf litter, and gentle flow.12
Food basics what goes in the bowl
A micropredator of tiny invertebrates. Offer small dried foods plus small live or frozen foods such as brine shrimp nauplii, moina and grindal worms.12
Company who they like around
Best in a group; at least 5 and ideally 10 or more, which spreads out the playful sparring between males.12
The story where it all began
Described by Albert Guenther in 1872, it is the type species of the pencilfish genus. It has been exported for aquariums since about 1910 and is one of the few pencilfish produced commercially, so it is widely available.123
Fun facts for the dinner table
- 1
It has been sold as an aquarium fish since around 1910.2
- 2
At night it takes on a barred pattern, and this rhythm happens even in blind fish, so it seems to be automatic.1
- 3
Several fish once named as separate species are now treated as colour forms of this one.1
- 4
Its courtship behaviour has been studied in detail by scientists.2
Recognised by the official bits
- IUCN Red List
- Least Concern (assessed September 2020)2
- FishBase
- Described by Guenther in 1872; type species of the genus Nannostomus2
The care rhythm Furry Diary remembers it for you
A typical home-care rhythm for a Golden Pencilfish. It is our own starting plan, not a vet's advice, and you can change every line in the app.
- FeedingSmall amounts once or twice a dayevery day
- Temperature checkevery day
- Water changeAbout 25% of the waterevery week
- Water testevery week
- Glass cleanevery week
- Filter rinseRinse in old tank water, never tap waterevery month
You might also like
Dwarf Pencilfish
Three-lined Pencilfish
Coral Red PencilfishLike what we are building? Buy us a coffee.
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Where this comes from
Every breed page shows where each fact comes from. If we got something wrong, sorry, we are pet people, not a science magazine. Tell us at support@furrydiary.app and we will fix it.
- Nannostomus beckfordi - Seriously Fish seriouslyfish.comused for origin, size, care, diet, behaviour, colours
- Nannostomus beckfordi summary - FishBase fishbase.seused for size, water parameters, IUCN, history
- Nannostomus - Wikipedia en.wikipedia.orgused for genus lifespan, commercial breeding
Checked 2026-09-30. Text is written in our own words from these sources.