Max Size: 6cm

Penguin Tetra (Thayeria boehlkei)

The Penguin Tetra is a peaceful, hardy and adaptable fish. They can be sensitive to nitrates but apart from that are relatively easy to care for and are ideal for beginners, and they make a lovely addition to an aquarium. This species does best in a densely planted aquarium.

The Penguin Tetra is usually olive with a prominent black line running down the lateral into the lower half of the tail fin, and its belly is silver in colour. Swimming and resting motions can be quite eye-catching, giving the fish a strong sense of individuality among other fish of similar size.


Penguin Tetras
Penguin Tetras
Penguin Tetra
Penguin Tetra
Penguin Tetras
Penguin Tetra
Penguin Tetra
Penguin Tetra
Penguin Tetra
Penguin Tetra
Quick Facts
Scientific NameThayeria boehlkei
Year Described1957
Other NamesHockey Stick Tetra and Blackline Tetra
OriginsBrazil, Peru
Aquarium LevelMiddle - Top
DifficultyBeginner - Intermediate
Best kept asGroups 5+
Lifespan3 - 5
Water Parameters
Water TypeFreshwater
PH6.0 - 8.0
GH4 -18
TDS71.43 - 32
72 - 82℉
22.2 - 27.8℃

Natural Habitat

Araguaia River


In the home aquarium, the Penguin Tetra 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

Adult females tend to display a duller, less intense colouration than the male and are more rounded in the belly.

Other Tetras of interest

Adonis Tetra(Lepidarchus adonis)
African Moon Tetra(Bathyaethiops caudomaculatus)
African Red Eyed Tetra(Arnoldichthys spilopterus)
Arowana Tetra(Gnathocharax steindachneri)
Black Darter Tetra(Poecilocharax weitzmani)
Black Line Tetra(Hyphessobrycon scholzei)
View all Tetras
Date Added: 21/07/2020 - Updated: 17/01/2023 13:30:49