Shoal & Stem
Back to Flora & Fauna

No photo yet

Sign in to submit the first photo

FisheasyFreshwater

Red Eye Tetra

Moenkhausia sanctaefilomenae

📍 South America

Ask Finn

The Red Eye Tetra is a small, schooling fish native to South America, easily recognized by its distinctive red eye and black spot near the tail. These peaceful community fish are hardy and adaptable, making them excellent choices for beginner to intermediate aquarists. They thrive in groups and display active, engaging behavior throughout the day.

Size2.2"
Min Tank20g
School6+
peaceful
Zonemiddle

Care Guide

Diet

Red Eye Tetras are omnivorous and should be fed a varied diet of high-quality flake foods, micro pellets, and occasional frozen foods such as brine shrimp and bloodworms. Feed small amounts 2-3 times daily, providing only what they can consume in 2-3 minutes. Occasional vegetable matter like blanched spinach supports digestive health.

Behavior

Red Eye Tetras are active, schooling fish that display constant movement and social interaction within their group. They are peaceful community fish that rarely exhibit aggression, though they may nip at very long-finned fish. These tetras are most active during daylight hours and prefer well-planted tanks with open swimming space.

Breeding

Breeding Red Eye Tetras in captivity is moderately difficult and requires separate breeding tanks with fine-leaved plants or spawning mops. Condition breeding pairs with live foods, then transfer to the breeding tank with slightly acidic, soft water. Parents should be removed after spawning as they may eat eggs; fry are very small and require infusoria or liquid fry food initially.

Common Diseases

Ich (Ichthyophthirius multifiliis)

Symptoms

White spots on body and fins, rapid breathing, rubbing against objects, lethargy

Treatment

Increase water temperature to 28-30°C (82-86°F), perform daily 25% water changes, use aquarium salt or commercial ich treatment; maintain for 10-14 days

Fin Rot

Symptoms

Frayed or deteriorating fins, discoloration at fin edges, lethargy, loss of appetite

Treatment

Perform 25-50% water changes, improve water quality, use antibacterial medication if severe; remove any sharp decorations that may cause injury

Neon Tetra Disease

Symptoms

Loss of coloration, curved spine, erratic swimming, lethargy, white stripe along lateral line

Treatment

No cure available; isolate affected fish to prevent spread, maintain pristine water conditions, euthanize severely affected individuals

Columnaris (Flexibacter columnaris)

Symptoms

White or grayish film on body, frayed fins, mouth rot, rapid breathing, loss of appetite

Treatment

Perform daily 50% water changes, use antibacterial medication, increase aeration, maintain temperature at 24-26°C (75-79°F); treat for 7-10 days

Community Photos

0 photos

Photos are added when members log a tank with this species and upload a photo in their tank journal. Add your own tank to contribute.

No photos yet — add a tank with Red Eye Tetra to be the first!

Sign in to vote.

Tips from the community 💡

0 tips

Real experiences, care advice, and keeper notes. Finn learns from these too.

Sign in to share your experience.

No community tips yet — be the first to share your knowledge!

Quick Facts

diet
omnivore - small flakes, micro pellets, and occasional frozen foods
lifespan
5-8 years
max size
5.5 cm (2.2 in)
tank size
20 gallons minimum
temperament
peaceful

Water it likes

ph
5.5-7.5
ammonia
0 ppm
nitrate
<20 ppm
hardness
2-15 dGH
temperature
72–82°F (22–28°C)

Stats

Community tips0
Kept by0 hobbyists