Max Size: 6cm

Redfin Penguin Tetra (Thayeria sp)

The Red Fin Penguin Tetra is a newly discovered member of the Penguin Tetra family. Tetras are peaceful fish, so they do not do well with boisterous or larger tankmates. Therefore, keeping them with other South American fish would be best.

It would be most beneficial to keep Red Fin Penguin Tetras in groups of at least six as they are schooling fish in nature. These Tetras will do much better when they are surrounded by other fish of the same species.

When kept in sufficient numbers, the fin-nipping behaviour of these Tetras does not usually emerge, as the fish focus on squabbling amongst themselves. However, like most Tetras, it looks far prettier and more effective when maintained like this, anyway.

Olive bodies and silver abdomens are the most common characteristics of Penguin Tetras, which also have a black line running down the side of the tail fin. Its new form displays fiery red fins and a champagne gold-like body colour, greatly enhancing its ornamental value.


Redfin Penguin Tetra
Quick Facts
Scientific NameThayeria sp
Other NamesNone
Aquarium LevelMiddle - Top
DifficultyBeginner - Intermediate
Best kept asGroups 6+
Lifespan3 - 5 years
Water Parameters
Water TypeFreshwater
PH5.5 - 8.0
GH5 - 20
73 - 82℉
22.8 - 27.8℃


In the home aquarium, the Redfin 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

It is very challenging to differentiate male from female Red Fin Penguin Tetras as both male and female fish have the same gorgeous body colour, which is one of its advantages. However, I can imagine when the females are in spawning their stomachs will look far more rounded than the males.

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: 29/01/2021 - Updated: 12/10/2022 13:11:08