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Freshwater fishes

The fish list

499 species, each with the water it needs, who it gets along with, and where it comes from. Find one, or browse by family, genus or river.

EndangeredRarePopularPeaceful✓ Small (6 cm or less)Calm waterStrong flow✓ SchoolingL-numbersWith photo Basic profiles too
Showing: River & region: Rio Negro ✕

Rio Negro 2 fish

Cardinal tetra

Cardinal tetra ≈

Tetras · ParacheirodonStaple

  • 23–29°C
  • pH 4.5–7
  • Calm
  • 1.6 in
  • Mid
  • Mixed
  • Peaceful
  • 6+ group!
Rio Negro and upper Orinoco, Brazil and Venezuela

Cardinal tetra

Paracheirodon axelrodi

Rio Negro and upper Orinoco, Brazil and Venezuela · blackwater stream

Temperature
23–29°C
pH
4.5–7
Adult size
1.6 in · 4 cm
Flow
Calm
Swims
Mid-water
Temperament
Peaceful
Diet
Omnivore
Group
6+
Typical price
$3–7
Rarity
Pet-store staple
View full profile

Photo: Paolo Neo, Public domain

Rummynose tetra

Rummynose tetra ≈

Tetras · HemigrammusStaple

  • 24–28°C
  • pH 5.5–7
  • Gentle
  • 2 in
  • Mid
  • Mixed
  • Peaceful
  • 8+ group!
Lower Amazon and Rio Negro, Brazil

Rummynose tetra

Hemigrammus rhodostomus

Lower Amazon and Rio Negro, Brazil · blackwater stream

Temperature
24–28°C
pH
5.5–7
Adult size
2 in · 5 cm
Flow
Gentle
Swims
Mid-water
Temperament
Peaceful
Diet
Omnivore
Group
8+
Typical price
$3–6
Rarity
Pet-store staple
View full profile

Photo: Gavinevans, CC BY-SA 3.0

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