Schooling freshwater fish: O
All schooling freshwater fish whose common name starts with O, in alphabetical order. Each card links to its care guide.
16 species
Odessa barb
Pethia padamya
Freshwater1.8 in (4.5 cm) · 20 gal (75 L)61–77°F (16–25°C)
Ogilbie's osteobrama
Rohtee ogilbii
Freshwater7.9 in (20 cm) · 66 gal (250 L)68–81°F (20–27°C)
Ogilby's rainbowfish
Melanotaenia ogilbyi
Freshwater3.1 in (8 cm) · 29 gal (110 L)75–84°F (24–29°C)
Oiapoque cory
Hoplisoma oiapoquense
Freshwater2.2 in (5.5 cm) · 20 gal (75 L)73–79°F (23–26°C)
One-lined pencilfish
Nannostomus unifasciatus
Freshwater1.6 in (4 cm) · 17 gal (65 L)73–82°F (23–28°C)
Onespot barb
Puntius terio
Freshwater3.1 in (8 cm) · 20 gal (75 L)68–79°F (20–26°C)
Orange chromide
Etroplus maculatus
FreshwaterBrackish3.9 in (10 cm) · 55 gal (210 L)68–82°F (20–28°C)
Orange Congo tetra
Phenacogrammus aurantiacus
Freshwater3.9 in (10 cm) · 42 gal (160 L)73–81°F (23–27°C)
Orange hatchet danio
Laubuka dadiburjori
Freshwater1.2 in (3 cm) · 13 gal (50 L)68–75°F (20–24°C)
Orange-finned danio
Danio kyathit
Freshwater2 in (5 cm) · 20 gal (75 L)68–79°F (20–26°C)
Orces's cory
Corydoras orcesi
Freshwater2.4 in (6 cm) · 20 gal (75 L)73–81°F (23–27°C)
Ornate cory
Brochis ornata
Freshwater2.8 in (7 cm) · 24 gal (90 L)72–79°F (22–26°C)
Ornate rainbowfish
Rhadinocentrus ornatus
Freshwater2.4 in (6 cm) · 20 gal (75 L)64–82°F (18–28°C)
Ornate tetra
Hyphessobrycon bentosi
Freshwater1.8 in (4.5 cm) · 20 gal (75 L)72–82°F (22–28°C)
Ortega's cory
Hoplisoma ortegai
Freshwater2 in (5 cm) · 16 gal (60 L)73–81°F (23–27°C)
Ourastigma cory
Corydoras ourastigma
Freshwater2.6 in (6.5 cm) · 20 gal (75 L)75–82°F (24–28°C)
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