Red Eye Tetra (Moenkhausia sanctaefilomenae) – Tank-Bred

The original Red Eye Tetra (Moenkhausia sanctaefilomenae) was first documented in South America, where it inhabits a range of slow-moving rivers and tributaries. These environments often feature soft substrates, submerged wood, and varying levels of vegetation.

This tank-bred variety has been raised in captivity for generations, resulting in a hardy and adaptable fish that retains the natural characteristics of the species while adjusting well to aquarium life.

Red Eye Tetras bring a steady, rhythmic movement to the aquarium, best experienced in a layout that gives them space to move while guiding their path through the tank. The goal is not to fill the aquarium, but to shape it—creating open water framed by structure.

As the school moves through the center, their silver bodies catch the light while their red eyes flash in unison, creating a subtle but consistent presence that ties the entire layout together.

Plants:

Use taller background plants like Vallisneria or Ludwigia to create vertical movement, while midground plants such as Anubias and Java Fern soften transitions along wood and stone. Floating plants like Frogbit or Salvinia can be added to diffuse light and create a calmer environment below.

Hardscape:

Driftwood and stone should be arranged to frame open swimming lanes rather than block them. Think of structure as a way to guide movement, allowing the school to pass through the aquascape rather than around it.

Botanicals:

Aquatic Arts botanicals such as Indian Almond Leaves or alder cones can be used sparingly to add natural texture and introduce light tannins. These elements help ground the aquarium, adding depth without disrupting the open, flowing design.

This species is an omnivore that readily accepts a wide range of foods. A staple diet of high-quality flake or micro pellet foods should be supplemented with frozen or live foods such as brine shrimp or daphnia to enhance coloration and overall health.

Red Eye Tetras do well with other active community fish such as tetras, rasboras, barbs, and peaceful bottom dwellers. Avoid housing with very small or delicate species, as their active nature may cause stress.

Generally safe with adult shrimp, though very small shrimp may be preyed upon.

Breeding is possible in captivity. They are egg scatterers and may spawn in well-conditioned aquariums with fine-leaved plants or spawning mops.

How many Red Eye Tetras should I keep together?

They should be kept in groups of at least 6, though larger groups will display stronger schooling behavior.

Are Red Eye Tetras aggressive?

They are generally peaceful but can be active and slightly boisterous, especially in smaller groups.

Do they nip fins?

They may occasionally nip fins if kept in too small of a group. Keeping them in proper numbers reduces this behavior.

What do they eat?

They accept flakes, pellets, and frozen foods, making them easy to feed.

Are they beginner-friendly?

Yes. Tank-bred specimens are hardy and adapt well to a variety of conditions.

Can they live with shrimp?

They are generally safe with adult shrimp, but very small shrimp may be at risk.

Do they need plants?

Plants are not required but help create a more natural and comfortable environment.

How active are they?

They are active swimmers and benefit from open space in the aquarium.

What makes them stand out?

Their red-ringed eyes and clean contrast give them a unique, understated appearance.

Why are mine chasing each other?

This is normal schooling and social behavior, especially in active groups.