Blue Danio Tank Mates

• African Dwarf Frog✅ Compatible
  Peaceful · 4 cm · Medium care · 22–26 °C (72–79 °F)
  • Both are peaceful; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
• Amapá Tetra✅ Compatible
  Peaceful · 4 cm · Medium care · 24–27 °C (75–81 °F)
  • Compatible on the things that matter: shared water near 24–26 °C, workable temperaments, and no predator-and-prey size gap.
  • Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Amapá Tetra in a shoal of 6+ or it gets stressed and nippy.
• Black Phantom Tetra✅ Compatible
  Peaceful · 4.5 cm · Easy care · 22–28 °C (72–82 °F)
  • Both are peaceful, and their water overlaps around 22–26 °C — no size, zone or temperament conflicts.
  • Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Black Phantom Tetra in a shoal of 6+ or it gets stressed and nippy.
• Blue Emperor Tetra✅ Compatible
  Peaceful · 4 cm · Medium care · 23–27 °C (73–81 °F)
  • Both are peaceful; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Blue Emperor Tetra in a shoal of 6+ or it gets stressed and nippy.
• Cardinal Tetra✅ Compatible
  Peaceful · 4 cm · Medium care · 23–27 °C (73–81 °F)
  • Both are peaceful; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Cardinal Tetra in a shoal of 6+ or it gets stressed and nippy.
• Emperor Tetra✅ Compatible
  Peaceful · 4 cm · Easy care · 23–27 °C (73–81 °F)
  • Both are peaceful, and their water overlaps around 23–26 °C — no size, zone or temperament conflicts.
  • Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Emperor Tetra in a shoal of 6+ or it gets stressed and nippy.
• Flame Tetra✅ Compatible
  Peaceful · 4 cm · Easy care · 22–28 °C (72–82 °F)
  • Compatible on the things that matter: shared water near 22–26 °C, workable temperaments, and no predator-and-prey size gap.
  • Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Flame Tetra in a shoal of 6+ or it gets stressed and nippy.
• Glowlight Tetra✅ Compatible
  Peaceful · 4 cm · Easy care · 22–28 °C (72–82 °F)
  • Both are peaceful; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Glowlight Tetra in a shoal of 6+ or it gets stressed and nippy.
• Gold Tetra✅ Compatible
  Peaceful · 4.5 cm · Easy care · 23–28 °C (73–82 °F)
  • Both are peaceful, and their water overlaps around 23–26 °C — no size, zone or temperament conflicts.
  • Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Gold Tetra in a shoal of 6+ or it gets stressed and nippy.
• Golden Dwarf Barb✅ Compatible
  Peaceful · 4 cm · Easy care · 18–24 °C (64–75 °F)
  • Both are peaceful, and their water overlaps around 21–24 °C — no size, zone or temperament conflicts.
  • Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Golden Dwarf Barb in a shoal of 6+ or it gets stressed and nippy.
• Jelly Bean Tetra✅ Compatible
  Peaceful · 4 cm · Medium care · 20–26 °C (68–79 °F)
  • Both are peaceful, and their water overlaps around 21–26 °C — no size, zone or temperament conflicts.
  • Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Jelly Bean Tetra in a shoal of 10+ or it gets stressed and nippy.
• Marbled Hatchetfish✅ Compatible
  Peaceful · 4 cm · Medium care · 23–28 °C (73–82 °F)
  • Both are peaceful, and their water overlaps around 23–26 °C — no size, zone or temperament conflicts.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Marbled Hatchetfish in a shoal of 6+ or it gets stressed and nippy.
• Otocinclus✅ Compatible
  Peaceful · 4 cm · Medium care · 21–26 °C (70–79 °F)
  • Both are peaceful, and their water overlaps around 21–26 °C — no size, zone or temperament conflicts.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Otocinclus in a shoal of 6+ or it gets stressed and nippy.
• Phoenix Tetra✅ Compatible
  Peaceful · 4 cm · Easy care · 23–28 °C (73–82 °F)
  • Both are peaceful, and their water overlaps around 23–26 °C — no size, zone or temperament conflicts.
  • Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Phoenix Tetra in a shoal of 8+ or it gets stressed and nippy.
• Purple Tetra✅ Compatible
  Peaceful · 4 cm · Medium care · 22–26 °C (72–79 °F)
  • Both are peaceful; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Purple Tetra in a shoal of 8+ or it gets stressed and nippy.
• Rainbow Emperor Tetra✅ Compatible
  Semi-aggressive · 3.6 cm · Medium care · 22–28 °C (72–82 °F)
  • Compatible on the things that matter: shared water near 22–26 °C, workable temperaments, and no predator-and-prey size gap.
  • Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Rainbow Emperor Tetra in a shoal of 8+ or it gets stressed and nippy.
• Red Phantom Tetra✅ Compatible
  Peaceful · 4 cm · Easy care · 22–28 °C (72–82 °F)
  • Both are peaceful, and their water overlaps around 22–26 °C — no size, zone or temperament conflicts.
  • Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Red Phantom Tetra in a shoal of 8+ or it gets stressed and nippy.
• Rosy Tetra✅ Compatible
  Peaceful · 4 cm · Easy care · 22–28 °C (72–82 °F)
  • Both are peaceful, and their water overlaps around 22–26 °C — no size, zone or temperament conflicts.
  • Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Rosy Tetra in a shoal of 6+ or it gets stressed and nippy.
• Rummy Nose Rasbora✅ Compatible
  Peaceful · 4 cm · Medium care · 20–26 °C (68–79 °F)
  • Both are peaceful; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Rummy Nose Rasbora in a shoal of 8+ or it gets stressed and nippy.
• Sparkling Gourami✅ Compatible
  Peaceful · 4 cm · Medium care · 24–28 °C (75–82 °F)
  • Both are peaceful, and their water overlaps around 24–26 °C — no size, zone or temperament conflicts.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
• Strawberry Betta✅ Compatible
  Peaceful · 4 cm · Medium care · 22–27 °C (72–81 °F)
  • Both are peaceful; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
• Threadfin Rainbowfish✅ Compatible
  Peaceful · 4 cm · Medium care · 24–28 °C (75–82 °F)
  • Both are peaceful, and their water overlaps around 24–26 °C — no size, zone or temperament conflicts.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Threadfin Rainbowfish in a shoal of 6+ or it gets stressed and nippy.
• Tiger Otocinclus✅ Compatible
  Peaceful · 4 cm · Medium care · 22–27 °C (72–81 °F)
  • Compatible on the things that matter: shared water near 22–26 °C, workable temperaments, and no predator-and-prey size gap.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Tiger Otocinclus in a shoal of 6+ or it gets stressed and nippy.
• Yellow Phantom Tetra✅ Compatible
  Peaceful · 4 cm · Easy care · 23–27 °C (73–81 °F)
  • Both are peaceful; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Yellow Phantom Tetra in a shoal of 6+ or it gets stressed and nippy.
• Black Darter Tetra⚠️ With caution
  Semi-aggressive · 4 cm · Hard care · 21–28 °C (70–82 °F)
  • Black Darter Tetra and Blue Danio are close in size, but the semi-aggressive one tends to dominate — add blue danio in a group to spread the pressure.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
• Black Ruby Barb⚠️ With caution
  Semi-aggressive · 6 cm · Easy care · 22–26 °C (72–79 °F)
  • Black Ruby Barb and Blue Danio are close in size, but the semi-aggressive one tends to dominate — add blue danio in a group to spread the pressure.
  • Your 75 L tank is below the ~100 L this pairing really wants — crowding raises aggression.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Black Ruby Barb in a shoal of 6+ or it gets stressed and nippy.
• Black Skirt Tetra⚠️ With caution
  Semi-aggressive · 6 cm · Easy care · 20–26 °C (68–79 °F)
  • Black Skirt Tetra is semi-aggressive and may chase or nip the smaller Blue Danio — plant heavily and break up sight lines.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Black Skirt Tetra in a shoal of 6+ or it gets stressed and nippy.
• Cherry Shrimp⚠️ With caution
  Peaceful · 3 cm · Easy care · 18–28 °C (64–82 °F)
  • Blue Danio may eat Cherry Shrimp or pick off its shrimplets — a densely planted tank with moss gives them a fighting chance.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Cherry Shrimp in a shoal of 10+ or it gets stressed and nippy.
• Chocolate Gourami⚠️ With caution
  Peaceful · 5 cm · Hard care · 25–30 °C (77–86 °F)
  • pH preferences only just meet (Blue Danio 6.5–7.5 vs Chocolate Gourami 4–6) — target the overlap and acclimate slowly.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Chocolate Gourami in a shoal of 6+ or it gets stressed and nippy.
• Fire Red Licorice Gourami⚠️ With caution
  Peaceful · 3.5 cm · Hard care · 23–28 °C (73–82 °F)
  • Water hardness preferences differ (Blue Danio 5–15 vs Fire Red Licorice Gourami 0–4 dGH).
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
• Ghost Shrimp⚠️ With caution
  Peaceful · 4 cm · Easy care · 18–28 °C (64–82 °F)
  • Blue Danio may eat Ghost Shrimp or pick off its shrimplets — a densely planted tank with moss gives them a fighting chance.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Ghost Shrimp in a shoal of 6+ or it gets stressed and nippy.
• Humpbacked Tetra⚠️ With caution
  Semi-aggressive · 5 cm · Hard care · 24–28 °C (75–82 °F)
  • Humpbacked Tetra and Blue Danio are close in size, but the semi-aggressive one tends to dominate — add blue danio in a group to spread the pressure.
  • Your 75 L tank is below the ~80 L this pairing really wants — crowding raises aggression.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Humpbacked Tetra in a shoal of 8+ or it gets stressed and nippy.
• Morse Code Corydoras⚠️ With caution
  Peaceful · 5 cm · Medium care · 23–26 °C (73–79 °F)
  • Your 75 L tank is below the ~80 L this pairing really wants — crowding raises aggression.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Morse Code Corydoras in a shoal of 6+ or it gets stressed and nippy.
• Serpae Tetra⚠️ With caution
  Semi-aggressive · 4 cm · Easy care · 23–28 °C (73–82 °F)
  • Serpae Tetra and Blue Danio are close in size, but the semi-aggressive one tends to dominate — add blue danio in a group to spread the pressure.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Serpae Tetra in a shoal of 6+ or it gets stressed and nippy.
• Silvertip Tetra⚠️ With caution
  Semi-aggressive · 5 cm · Easy care · 22–28 °C (72–82 °F)
  • Silvertip Tetra is semi-aggressive and may chase or nip the smaller Blue Danio — plant heavily and break up sight lines.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Silvertip Tetra in a shoal of 6+ or it gets stressed and nippy.
• Spotfin Betta⚠️ With caution
  Semi-aggressive · 5 cm · Medium care · 23–28 °C (73–82 °F)
  • Spotfin Betta is semi-aggressive and may chase or nip the smaller Blue Danio — plant heavily and break up sight lines.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
• Striped Red-Eye Puffer⚠️ With caution
  Aggressive · 5 cm · Hard care · 24–28 °C (75–82 °F)
  • Striped Red-Eye Puffer and Blue Danio are close in size, but the aggressive one tends to dominate — add blue danio in a group to spread the pressure.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
• Tiger Badis⚠️ With caution
  Semi-aggressive · 4 cm · Medium care · 22–24 °C (72–75 °F)
  • Tiger Badis and Blue Danio are close in size, but the semi-aggressive one tends to dominate — add blue danio in a group to spread the pressure.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
• Tiger Shrimp⚠️ With caution
  Peaceful · 3 cm · Hard care · 20–25 °C (68–77 °F)
  • Blue Danio may eat Tiger Shrimp or pick off its shrimplets — a densely planted tank with moss gives them a fighting chance.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
  • Keep Tiger Shrimp in a shoal of 6+ or it gets stressed and nippy.
• Wine Red Betta⚠️ With caution
  Aggressive · 5 cm · Medium care · 24–28 °C (75–82 °F)
  • One likes softer water and the other harder (5–15 vs 0–4 dGH) — a compromise, not a perfect match.
  • Expect Wine Red Betta to harass Blue Danio at times; give dense cover and watch them at feeding.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
• Alligator Gar⛔ Not recommended
  Aggressive · 250 cm · Hard care · 24–28 °C (75–82 °F)
  • Blue Danio is bite-sized to a 250 cm predatory alligator gar — it will be eaten.
  • Expect Alligator Gar to harass Blue Danio at times; give dense cover and watch them at feeding.
  • Your 75 L tank is below the ~3785 L this pairing really wants — crowding raises aggression.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
• Clown Knifefish⛔ Not recommended
  Aggressive · 90 cm · Hard care · 24–28 °C (75–82 °F)
  • Clown Knifefish (90 cm) is big enough to swallow the 4 cm Blue Danio whole.
  • Expect Clown Knifefish to harass Blue Danio at times; give dense cover and watch them at feeding.
  • Your 75 L tank is below the ~750 L this pairing really wants — crowding raises aggression.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
• Fire Eel⛔ Not recommended
  Semi-aggressive · 100 cm · Medium care · 24–28 °C (75–82 °F)
  • Size gap is too large (100 vs 4 cm): Fire Eel will treat Blue Danio as food.
  • Expect Fire Eel to harass Blue Danio at times; give dense cover and watch them at feeding.
  • Your 75 L tank is below the ~380 L this pairing really wants — crowding raises aggression.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
• Koi⛔ Not recommended
  Peaceful · 90 cm · Medium care · 4–28 °C (39–82 °F)
  • Size gap is too large (90 vs 4 cm): Koi will treat Blue Danio as food.
  • Your 75 L tank is below the ~3800 L this pairing really wants — crowding raises aggression.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
• Redtail Catfish⛔ Not recommended
  Aggressive · 120 cm · Hard care · 24–27 °C (75–81 °F)
  • Size gap is too large (120 vs 4 cm): Redtail Catfish will treat Blue Danio as food.
  • Redtail Catfish clearly outsizes Blue Danio and is aggressive; risky unless the tank is big and well-planted.
  • Your 75 L tank is below the ~5700 L this pairing really wants — crowding raises aggression.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
• Spotted Gar⛔ Not recommended
  Aggressive · 90 cm · Hard care · 18–26 °C (64–79 °F)
  • Size gap is too large (90 vs 4 cm): Spotted Gar will treat Blue Danio as food.
  • Spotted Gar is aggressive and may chase or nip the smaller Blue Danio — plant heavily and break up sight lines.
  • Your 75 L tank is below the ~600 L this pairing really wants — crowding raises aggression.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
• Wels Catfish⛔ Not recommended
  Aggressive · 300 cm · Hard care · 15–25 °C (59–77 °F)
  • Size gap is too large (300 vs 4 cm): Wels Catfish will treat Blue Danio as food.
  • Wels Catfish clearly outsizes Blue Danio and is aggressive; risky unless the tank is big and well-planted.
  • Your 75 L tank is below the ~20000 L this pairing really wants — crowding raises aggression.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.
• Wolf Cichlid⛔ Not recommended
  Aggressive · 72 cm · Hard care · 24–30 °C (75–86 °F)
  • Blue Danio is bite-sized to a 72 cm predatory wolf cichlid — it will be eaten.
  • Wolf Cichlid is aggressive and may chase or nip the smaller Blue Danio — plant heavily and break up sight lines.
  • Your 75 L tank is below the ~760 L this pairing really wants — crowding raises aggression.
  • Keep Blue Danio in a shoal of 6+ or it gets stressed and nippy.

Compatibility is computed from each species' care data — a strong starting point, not a guarantee. Individual temperament varies, so always introduce new fish slowly and watch them.