Max Size: 3cm

Barred Pencilfish (Nannostomus espei)

Barred Pencilfish are a peaceful, good looking and somewhat shy species that are sought after in the aquarium hobby, although they are usually quite expensive to buy. However, this pencilfish is unsuitable for the general community aquarium due to its small size and timid nature.

Ideally, you should maintain these fish in a species only aquarium or in an aquarium with small peaceful non-aggressive fish such as Characids and smaller Catfish. These Pencilfish also make an ideal dither fish for Apistogrammas.

Though sociable by nature, Barred Pencilfish are a shoaling species rather than schooling; therefore, they should be kept in a group of at least ten individuals. Keeping these fish in more significant numbers will allow them to show more natural behaviour and will also help reduce aggression between individuals. For example, it's not uncommon to see nipped fins within a group; however, this behaviour does not usually spread to tankmates.

Ideally, it would be best if you kept Barred Pencilfish in a heavily-planted aquarium with a dark substrate and lots of hiding places to provide broken lines of sight. Floating plants are a valuable addition to help subdue the light, as is dried leaf litter and driftwood branches. These fish enjoy a slow current, so using an air-powered sponge filter would be best to provide gentle filtration.

Barred Pencilfish require stable water conditions; therefore, you should never add them to a biologically immature aquarium.

There are five broad, comma-like blotches on each flank of the Barred Pencilfish. Adipose fins are also present on these fish, which are not present on many pencilfish. As with all pencilfish, they have a small mouth that is always open. Additionally, the anal fin has a relatively short base, but the majority of males have an enlarged, well-developed anal fin used for courtship and spawning.


Barred Pencilfish
Barred Pencilfish
Barred Pencilfish
Barred Pencilfish
Quick Facts
Scientific NameNannostomus espei
Other NamesEspe's Pencilfish, Four-barred Pencilfish, Banded Pencilfish
Aquarium LevelMiddle - Top
DifficultyBeginner - Intermediate
Best kept asGroups 10+
Lifespan3 - 5 years
Water Parameters
Water TypeFreshwater
PH5.0 - 7.0
GH4 - 10
TDS18 - 90
71 - 82℉
21.7 - 27.8℃


In the home aquarium, the Barred Pencilfish will readily accept most good quality dried foods such as granules, flakes and sinking pellets. These modern food products have been developed to provide all adequate nutrition to maintain your fish's health and dietary requirements.

Providing additional foodstuffs such as live, frozen, and freeze-dried meals such as bloodworm, daphnia, and tubifex once or twice a week will provide additional benefits to your fish's health and well-being but is not a must for this fish.

It should be noted that bloodworms should only be given as an occasional treat and should not be used as the staple diet as they are difficult for fish to digest and can potentially cause blockages.

This fish is an omnivore in the wild, meaning it will consume some vegetable matter. Although most modern fish foods take this into account and include them in their products, you can still supplement your fish's diet with blanched vegetables such as spinach, broccoli, and zucchini. Ensure you do not overfeed your fish and remove any leftovers the following day.

Sexual Dimorphism

It is relatively straightforward to differentiate between male and female Barred Pencilfish. Males are usually slightly slimmer and more colourful than females. In contrast, females have rounded bodies, and the gold colour is much duller than that of males.

Other Pencilfish of interest

Cenepa Red Pencilfish(Nannstomus sp)
Coral Red Pencilfish(Nannostomus mortenthaleri)
Dwarf Pencilfish(Nannostomus marginatus)
Golden Pencilfish(Nannostomus beckfordi)
Hockeystick Pencilfish(Nannostomus eques)
Purple Pencilfish(Nannostomus rubrocaudatus)
View all Pencilfish
Date Added: 02/02/2022 13:05:44 - Updated: 20/09/2022 15:14:10