Max Size: 7cm

Red Eye Tetra (Moenkhausia sanctaefilomenae)

The Red Eye Tetra is peaceful, very active, relatively hardy and easy to take care of as they can adapt to a wide range of water parameters, making them perfect for a beginner aquarist who wants to add a touch of elegance to a community aquarium. These Tetras are tough enough to be indecisive and big enough not to get eaten by other species with a big mouth.

Red Eye Tetras are schooling fish in nature, so they should be kept in a group of at least six individuals, preferably more. Keeping these Tetras in more significant numbers will give you a better looking natural display. However, if you keep these Tetras in too small a group, they may become withdrawn and start to show aggression to other fish species.

Ideal tankmates for Red Eye Tetras could include other similarly sized Tetras, larger Rasboras, Rainbowfish, Barbs, and most Danios. In addition, bottom dwellers such as Corydoras Catfish and Botia Loaches will also make excellent tankmates.

Red Eye Tetras can also be used as a dither fish for non-agressive medium-sized Cichlids. However, it would be best if you avoided slower, more timid species such as Gouramis and Dwarf Cichlids; otherwise, they will feel intimidated by their boisterous activity.

Red Eye Tetras will thrive in most well-maintained tanks, although these fish do not like very bright lighting or lightly decorated surroundings.

Red Eye Tetras would look stunning in either a well-planted aquarium or an aquarium designed to mimic an Amazonian biotope setup. You will need a sandy substrate, driftwood branches, and twisted roots to achieve this result. It would also be beneficial to add dried leaves such as beech or oak, as this will add to the natural feel.

The Red Eye Tetra has a bright silver body accentuated by black colouring on the base of the caudal fin edged with white. In addition, these Tetras have a thin bright red circle around their eye.


Red Eye Tetra
Red Eye Tetras
Red Eye Tetras Spawning
Eye Tetra Fish
Red Eye Tetra
Red Eye Tetra
Red Eye Tetra
Quick Facts
Scientific NameMoenkhausia sanctaefilomenae
Year Described1907
Other Nameslamp eye tetra.
OriginsArgentina, Brazil, Paraguay, Uruguay
Aquarium LevelMiddle - Top
Best kept asGroups 5+
Lifespan3 - 5 years
Water Parameters
Water TypeFreshwater
PH5.5 - 8.5
GH5 - 20
KH4 - 8
TDS100 - 200
75 - 85℉
23.9 - 29.4℃

Natural Habitat

São Francisco River


In the home aquarium, the Red Eye 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.

Tank Mates

2 interesting tank mate ideas for the Red Eye Tetra could include:

Black Widow Tetra(Gymnocorymbus ternetzi)
Denison Barb(Sahyadria denisonii)

Sexual Dimorphism

It can be somewhat challenging to differentiate between the male and female Red Eye Tetra. However, the females are often slightly larger and are much more rounder in the stomach than males, especially when they are full of eggs.

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: 28/05/2020 - Updated: 15/03/2022 17:30:30