Max Size: 3.5cm

Exclamation Mark Tetra (Bryconella pallidifrons)

Exclamation Mark Tetras are very small, peaceful and fragile shoaling fish that are relatively rare and not commonly seen in the hobby.

These Tetras are perfect for the nano or well-planted aquarium. However, due to their size and delicate nature, it would be best to keep them with their own kind. However, these Tetras may do okay if you have a large community aquarium with only small peaceful species. Males can sometimes be quarrelsome with their own kind, but it is nothing to worry about as no actual harm will follow.

Exclamation Mark Tetras are a true blackwater fish; therefore, filtering through peat can be very helpful. In addition to improving the chemical parameters, peat's bactericidal effect also reduces the aquarium's bacterial load. Adding dried leaves to the bottom of the aquarium, such as Indian almond or oak, can achieve the blackwater look in your home aquarium, as can driftwood and alder cones. As a result, the water will gradually darken and mimic the water in its natural habitat.

Currently, there is little to no information about the Exclamation Mark Tetra; however, they have a silvery transparent body with a black and gold longitudinal line that ends at the caudal fin. The end of the longitudinal line gets slightly wider as it comes to a holt giving the appearance of a small patch that ends up forming what looks like an exclamation mark hence the name.

Tank Mates

1 ideal tank mate ideas for the Exclamation Mark Tetra include:

Red Rili Shrimp(Neocaridina davidi var)
Quick Facts
Scientific NameBryconella pallidifrons
Other NamesBryconella Tetra, Thread Tetra
OriginsBrazil, Colombia
Aquarium LevelMiddle - Top
Best kept asGroups 8+
Lifespan3 - 5 years
Water Parameters
Water TypeFreshwater
PH6.0 - 7.5
GH5 - 10
KH2 - 4
78 - 82℉
25.6 - 27.8℃


Exclamation Mark Tetra
Exclamation Mark Tetra

Natural Habitat

You can find Exclamation Mark Tetras in the Yahuacaca River in Southern Colombia and Brazil in South America. They inhabit medium flowing, soft, acidic clear blackwater rivers and streams with substrates containing pebbles, leaf litter and driftwood roots and branches.


Exclamation Mark Tetras will accept virtually any form of aquarium food; However, when first introduced into the aquarium, they may shy away from food initially, so provide them with live food.

Once settled into the aquarium, it would be best to provide your Tetras with a balanced diet of high-quality dried food such as flakes, pellets and granules supplemented with frozen and live food such as daphnia, brine shrimp, Tubifex and bloodworm. It would also be beneficial to your fish if you gave them occasional green vegetables in their diet as this will help promote the best colour and health for your fish.

Sexual Dimorphism

It can be somewhat challenging to differentiate between the male and female Exclamation Mark Tetra. However, the males are slightly smaller than females and somewhat slimmer, whereas females have more rounded abdomens and are more significant than males.


Unfortunately, there is limited to no information on the breeding habits of Exclamation Mark Tetras.

Other Tetras of interest

African Moon Tetra(Bathyaethiops caudomaculatus)
African Red Eyed Tetra(Arnoldichthys spilopterus)
Black Darter Tetra(Poecilocharax weitzmani)
Black Line Tetra(Hyphessobrycon scholzei)
Black Neon Tetra(Hyphessobrycon herbertaxelrodi)
Black Phantom Tetra(Hyphessobrycon megalopterus)
View all Tetras
Date Added: 03/12/2021 15:41:43 - Updated: 03/12/2021 16:33:43