Red Moenkhausia / Rubra Tetra (Moenkhausia rubra)

Moenkhausia rubra

(Red Moenkhausia / Rubra Tetra)

A newer, lesser-known South American tetra that has serious potential as a premium nano-community fish.

Quick ID

• Scientific name: Moenkhausia rubra
• Family: Characidae (true tetras)
• Origin: Brazil – upper Tapajós basin (Amazon system) 

 Still relatively rare in the trade 

Size & lifespan

• Size:
  • ~5 cm (2") typical aquarium size 
  • Max reported: ~5.4 cm 
• Lifespan: ~3–5 years (typical tetra range)

Appearance

• Base: silver body
• Highlights:
  • Red / orange tones in fins and body
  • Subtle metallic sheen
• Color intensifies:
  • When breeding
  • In groups
  • In good water conditions 

Behavior

• Peaceful schooling fish 
• Needs:
• 10+ group minimum (very important)
• Active mid-level swimmer
•  Calm Social Good for display tanks
• Better behavior and color in larger schools

Water parameters

• Temp: 23–28°C (74–82°F) 
• pH: 6.0–7.5 
• Water: soft → moderate hardness

 Easy fit for:

• Standard tropical setups
• Planted tanks

Tank setup

• Minimum: ~15–20 gallons for a school
• Best setup:
  • Plants (Java moss, swords, Anubias)
  • Driftwood + shaded areas
  • Open mid-water swimming space

 Natural habitat:

• Slow rivers/streams with vegetation 

Diet

• Omnivore:
  • Flake / micro pellets
  • Frozen/live (brine shrimp, daphnia, bloodworms) 

 Easy feeder → no special requirements

Compatibility

Works with

• Other tetras
• Rasboras
• Corydoras
• Dwarf cichlids
• Shrimp (mostly safe)

 Avoid

• Aggressive fish
• Big predators

 Very classic community tetra behavior

Breeding

• Egg scatterer (typical tetra)
• Easy to spawn in good conditions 

Will breed in planted tanks
Eggs/fry get eaten unless separated