Cochu's Blue Tetra Tank Mates

Cochu's Blue Tetra is peaceful, so its tank mates need choosing with care. Here are the 139 freshwater species that pair well with a cochu's blue tetra — plus the 73 to avoid — with a live checker you can tune to your own tank.

By The Aquarium DB Team • Updated June 8, 2026 • Full Cochu's Blue Tetra care guide →
Best matches

The best tank mates for a cochu's blue tetra

  • Ember Tetra ✅ Compatible
    Easy care · Peaceful · 2 cm · 24–28 °C (75–82 °F)
    Both are peaceful; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Neon Green Rasbora ✅ Compatible
    Easy care · Peaceful · 2 cm · 22–26 °C (72–79 °F)
    Both are peaceful, and their water overlaps around 22–26 °C — no size, zone or temperament conflicts.
  • Ramshorn Snail ✅ Compatible
    Easy care · Peaceful · 2 cm · 20–28 °C (68–82 °F)
    Both are peaceful, and their water overlaps around 22–28 °C — no size, zone or temperament conflicts.
  • Red Lip Nerite Snail ✅ Compatible
    Easy care · Peaceful · 2 cm · 22–28 °C (72–82 °F)
    Compatible on the things that matter: shared water near 22–28 °C, workable temperaments, and no predator-and-prey size gap.
  • Dawn Tetra ✅ Compatible
    Easy care · Peaceful · 2.5 cm · 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.
  • Nerite Snail ✅ Compatible
    Easy care · Peaceful · 2.5 cm · 22–28 °C (72–82 °F)
    Compatible on the things that matter: shared water near 22–28 °C, workable temperaments, and no predator-and-prey size gap.
  • Assassin Snail ✅ Compatible
    Easy care · Peaceful · 3 cm · 22–26 °C (72–79 °F)
    Both are peaceful, and their water overlaps around 22–26 °C — no size, zone or temperament conflicts.
  • Endler's Livebearer ✅ Compatible
    Easy care · Peaceful · 3 cm · 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.
  • Glowlight Danio ✅ Compatible
    Easy care · Peaceful · 3 cm · 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.
  • Gold Ring Danio ✅ Compatible
    Easy care · Peaceful · 3 cm · 18–26 °C (64–79 °F)
    Compatible on the things that matter: shared water near 22–26 °C, workable temperaments, and no predator-and-prey size gap.
  • Malaysian Trumpet Snail ✅ Compatible
    Easy care · Peaceful · 3 cm · 21–27 °C (70–81 °F)
    Both are peaceful, and their water overlaps around 22–27 °C — no size, zone or temperament conflicts.
  • Neon Tetra ✅ Compatible
    Easy care · Peaceful · 3 cm · 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.
  • Tail-spot Corydoras ✅ Compatible
    Easy care · Peaceful · 3 cm · 22–28 °C (72–82 °F)
    Both are peaceful, and their water overlaps around 22–28 °C — no size, zone or temperament conflicts.
  • Trinidad Guppy ✅ Compatible
    Easy care · Peaceful · 3 cm · 19–24 °C (66–75 °F)
    Both are peaceful, and their water overlaps around 22–24 °C — no size, zone or temperament conflicts.
  • Pygmy Corydoras ✅ Compatible
    Easy care · Peaceful · 3.2 cm · 22–26 °C (72–79 °F)
    Compatible on the things that matter: shared water near 22–26 °C, workable temperaments, and no predator-and-prey size gap.
  • Glowlight Rasbora ✅ Compatible
    Easy care · Peaceful · 3.5 cm · 23–28 °C (73–82 °F)
    Both are peaceful; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Blue Danio ✅ Compatible
    Easy care · Peaceful · 4 cm · 21–26 °C (70–79 °F)
    Both are peaceful, and their water overlaps around 22–26 °C — no size, zone or temperament conflicts.
  • Emperor Tetra ✅ Compatible
    Easy care · Peaceful · 4 cm · 23–27 °C (73–81 °F)
    Compatible on the things that matter: shared water near 23–27 °C, workable temperaments, and no predator-and-prey size gap.
  • Flame Tetra ✅ Compatible
    Easy care · Peaceful · 4 cm · 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.
  • Glowlight Tetra ✅ Compatible
    Easy care · Peaceful · 4 cm · 22–28 °C (72–82 °F)
    Both are peaceful, and their water overlaps around 22–28 °C — no size, zone or temperament conflicts.
  • Golden Dwarf Barb ✅ Compatible
    Easy care · Peaceful · 4 cm · 18–24 °C (64–75 °F)
    Both are peaceful; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Phoenix Tetra ✅ Compatible
    Easy care · Peaceful · 4 cm · 23–28 °C (73–82 °F)
    Both are peaceful, and their water overlaps around 23–28 °C — no size, zone or temperament conflicts.
  • Red Phantom Tetra ✅ Compatible
    Easy care · Peaceful · 4 cm · 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.
  • Rosy Tetra ✅ Compatible
    Easy care · Peaceful · 4 cm · 22–28 °C (72–82 °F)
    Compatible on the things that matter: shared water near 22–28 °C, workable temperaments, and no predator-and-prey size gap.
With caution

Cochu's Blue Tetra tank mates that can work with care

  • Afra Cichlid ⚠️ With caution
    Medium care · Semi-aggressive · 10 cm · 24–28 °C (75–82 °F)
    Different pH ranges (5.5–7.5 vs 7.8–8.6); doable if you sit in the shared band, but not ideal long-term.
  • African Butterfly Cichlid ⚠️ With caution
    Medium care · Semi-aggressive · 8 cm · 22–28 °C (72–82 °F)
    African Butterfly Cichlid is semi-aggressive and may chase or nip the smaller Cochu's Blue Tetra — plant heavily and break up sight lines.
  • Agassiz's Dwarf Cichlid ⚠️ With caution
    Medium care · Semi-aggressive · 9 cm · 24–30 °C (75–86 °F)
    Expect Agassiz's Dwarf Cichlid to harass Cochu's Blue Tetra at times; give dense cover and watch them at feeding.
  • Amano Shrimp ⚠️ With caution
    Easy care · Peaceful · 5 cm · 18–28 °C (64–82 °F)
    Cochu's Blue Tetra may eat Amano Shrimp or pick off its shrimplets — a densely planted tank with moss gives them a fighting chance.
  • Amazon Puffer ⚠️ With caution
    Medium care · Peaceful · 8 cm · 23–28 °C (73–82 °F)
    Your 75 L tank is below the ~120 L this pairing really wants — crowding raises aggression.
  • Angelfish ⚠️ With caution
    Medium care · Semi-aggressive · 15 cm · 24–30 °C (75–86 °F)
    Angelfish clearly outsizes Cochu's Blue Tetra and is semi-aggressive; risky unless the tank is big and well-planted.
  • Arrowhead Puffer ⚠️ With caution
    Hard care · Aggressive · 12 cm · 23–28 °C (73–82 °F)
    Arrowhead Puffer is aggressive and may chase or nip the smaller Cochu's Blue Tetra — plant heavily and break up sight lines.
  • Ash Lipped Apisto ⚠️ With caution
    Hard care · Semi-aggressive · 7 cm · 24–29 °C (75–84 °F)
    Expect Ash Lipped Apisto to harass Cochu's Blue Tetra at times; give dense cover and watch them at feeding.

+ 120 more “with caution” pairings — see the interactive checker above.

Avoid

Fish to avoid keeping with a cochu's blue tetra

  • Wels Catfish ⛔ Avoid
    Hard care · Aggressive · 300 cm · 15–25 °C (59–77 °F)
    Wels Catfish (300 cm) is big enough to swallow the 5 cm Cochu's Blue Tetra whole.
  • Alligator Gar ⛔ Avoid
    Hard care · Aggressive · 250 cm · 24–28 °C (75–82 °F)
    Cochu's Blue Tetra is bite-sized to a 250 cm predatory alligator gar — it will be eaten.
  • Redtail Catfish ⛔ Avoid
    Hard care · Aggressive · 120 cm · 24–27 °C (75–81 °F)
    Size gap is too large (120 vs 5 cm): Redtail Catfish will treat Cochu's Blue Tetra as food.
  • Fire Eel ⛔ Avoid
    Medium care · Semi-aggressive · 100 cm · 24–28 °C (75–82 °F)
    Cochu's Blue Tetra is bite-sized to a 100 cm predatory fire eel — it will be eaten.
  • Clown Knifefish ⛔ Avoid
    Hard care · Aggressive · 90 cm · 24–28 °C (75–82 °F)
    Size gap is too large (90 vs 5 cm): Clown Knifefish will treat Cochu's Blue Tetra as food.
  • Koi ⛔ Avoid
    Medium care · Peaceful · 90 cm · 4–28 °C (39–82 °F)
    Koi (90 cm) is big enough to swallow the 5 cm Cochu's Blue Tetra whole.
  • Spotted Gar ⛔ Avoid
    Hard care · Aggressive · 90 cm · 18–26 °C (64–79 °F)
    Size gap is too large (90 vs 5 cm): Spotted Gar will treat Cochu's Blue Tetra as food.
  • Wolf Cichlid ⛔ Avoid
    Hard care · Aggressive · 72 cm · 24–30 °C (75–86 °F)
    Size gap is too large (72 vs 5 cm): Wolf Cichlid will treat Cochu's Blue Tetra as food.

+ 65 more to avoid — the checker above flags every one.

Interactive tool

Check any fish against a cochu's blue tetra

Dial in your exact tank size and filter by result — the checker scores every species in our database against a cochu's blue tetra, with the reasoning for each verdict.

Tank-mate checker

Will it live with a Cochu's Blue Tetra?

We compare each fish against your cochu's blue tetra on temperament, size, water parameters and swimming zone. Set your tank size and filter the results.

  • Adolf's Cory✅ Compatible
    Peaceful · 5.5 cm · Medium care · 22–26 °C (72–79 °F)
    • Both are peaceful, and their water overlaps around 22–26 °C — no size, zone or temperament conflicts.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Adolf's Cory in a shoal of 6+ or it gets stressed and nippy.
  • Axelrod's Cory✅ Compatible
    Peaceful · 5 cm · Easy care · 23–28 °C (73–82 °F)
    • Compatible on the things that matter: shared water near 23–28 °C, workable temperaments, and no predator-and-prey size gap.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Axelrod's Cory in a shoal of 6+ or it gets stressed and nippy.
  • Bandit Corydoras✅ Compatible
    Peaceful · 5 cm · Easy care · 22–27 °C (72–81 °F)
    • Both are peaceful, and their water overlaps around 22–27 °C — no size, zone or temperament conflicts.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Bandit Corydoras in a shoal of 6+ or it gets stressed and nippy.
  • Blue Turbo Snail✅ Compatible
    Peaceful · 5 cm · Medium care · 25–30 °C (77–86 °F)
    • Both are peaceful; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
  • Checkered Barb✅ Compatible
    Peaceful · 5 cm · Easy care · 20–25 °C (68–77 °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 Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Checkered Barb in a shoal of 6+ or it gets stressed and nippy.
  • Cherry Barb✅ Compatible
    Peaceful · 5 cm · Easy care · 23–27 °C (73–81 °F)
    • Compatible on the things that matter: shared water near 23–27 °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 Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Cherry Barb in a shoal of 6+ or it gets stressed and nippy.
  • Chocolate Gourami✅ Compatible
    Peaceful · 5 cm · Hard care · 25–30 °C (77–86 °F)
    • Compatible on the things that matter: shared water near 25–28 °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 Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Chocolate Gourami in a shoal of 6+ or it gets stressed and nippy.
  • Firehead Tetra✅ Compatible
    Peaceful · 5 cm · Medium care · 24–28 °C (75–82 °F)
    • Both are peaceful, and their water overlaps around 24–28 °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 Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Firehead Tetra in a shoal of 8+ or it gets stressed and nippy.
  • Five-banded Barb✅ Compatible
    Peaceful · 5 cm · Easy care · 23–27 °C (73–81 °F)
    • Both are peaceful, and their water overlaps around 23–27 °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 Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Five-banded Barb in a shoal of 6+ or it gets stressed and nippy.
  • Forktail Blue-eye✅ Compatible
    Peaceful · 5 cm · Easy care · 22–28 °C (72–82 °F)
    • Compatible on the things that matter: shared water near 22–28 °C, workable temperaments, and no predator-and-prey size gap.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Forktail Blue-eye in a shoal of 6+ or it gets stressed and nippy.
  • Half-striped Penguin Tetra✅ Compatible
    Peaceful · 5 cm · Medium care · 23–28 °C (73–82 °F)
    • Compatible on the things that matter: shared water near 23–28 °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 Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Half-striped Penguin Tetra in a shoal of 6+ or it gets stressed and nippy.
  • Harlequin Rasbora✅ Compatible
    Peaceful · 5 cm · Easy care · 23–28 °C (73–82 °F)
    • Both are peaceful, and their water overlaps around 23–28 °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 Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Harlequin Rasbora in a shoal of 6+ or it gets stressed and nippy.
  • Honey Gourami✅ Compatible
    Peaceful · 5 cm · Easy care · 22–28 °C (72–82 °F)
    • Compatible on the things that matter: shared water near 22–28 °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 Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
  • Horseman Cory✅ Compatible
    Peaceful · 5 cm · Medium care · 22–26 °C (72–79 °F)
    • Compatible on the things that matter: shared water near 22–26 °C, workable temperaments, and no predator-and-prey size gap.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Horseman Cory in a shoal of 6+ or it gets stressed and nippy.
  • Japanese Trapdoor Snail✅ Compatible
    Peaceful · 5 cm · Easy care · 10–28 °C (50–82 °F)
    • Compatible on the things that matter: shared water near 22–28 °C, workable temperaments, and no predator-and-prey size gap.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
  • Julii Corydoras✅ Compatible
    Peaceful · 5 cm · Easy care · 23–26 °C (73–79 °F)
    • Both are peaceful, and their water overlaps around 23–26 °C — no size, zone or temperament conflicts.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Julii Corydoras in a shoal of 6+ or it gets stressed and nippy.
  • Masked Corydoras✅ Compatible
    Peaceful · 5 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.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Masked Corydoras in a shoal of 6+ or it gets stressed and nippy.
  • Mystery Snail✅ Compatible
    Peaceful · 5 cm · Easy care · 20–28 °C (68–82 °F)
    • Both are peaceful; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
  • Panda Corydoras✅ Compatible
    Peaceful · 5 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.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Panda Corydoras in a shoal of 6+ or it gets stressed and nippy.
  • Rummy-nose Tetra✅ Compatible
    Peaceful · 5 cm · Medium care · 23–29 °C (73–84 °F)
    • Compatible on the things that matter: shared water near 23–28 °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 Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Rummy-nose Tetra in a shoal of 6+ or it gets stressed and nippy.
  • Skunk Corydoras✅ Compatible
    Peaceful · 5 cm · Easy care · 22–26 °C (72–79 °F)
    • Both are peaceful, and their water overlaps around 22–26 °C — no size, zone or temperament conflicts.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Skunk Corydoras in a shoal of 6+ or it gets stressed and nippy.
  • Stoliczka's Barb✅ Compatible
    Peaceful · 5 cm · Easy care · 20–26 °C (68–79 °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 Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Stoliczka's Barb in a shoal of 6+ or it gets stressed and nippy.
  • Xingu Black Neon Tetra✅ Compatible
    Peaceful · 5 cm · Medium care · 24–28 °C (75–82 °F)
    • Compatible on the things that matter: shared water near 24–28 °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 Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Xingu Black Neon Tetra in a shoal of 8+ or it gets stressed and nippy.
  • Zebra Danio✅ Compatible
    Peaceful · 5 cm · Easy care · 18–25 °C (64–77 °F)
    • Both are peaceful, and their water overlaps around 22–25 °C — no size, zone or temperament conflicts.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Zebra Danio in a shoal of 6+ or it gets stressed and nippy.
  • Amano Shrimp⚠️ With caution
    Peaceful · 5 cm · Easy care · 18–28 °C (64–82 °F)
    • Cochu's Blue Tetra may eat Amano Shrimp or pick off its shrimplets — a densely planted tank with moss gives them a fighting chance.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
  • Black Ruby Barb⚠️ With caution
    Semi-aggressive · 6 cm · Easy care · 22–26 °C (72–79 °F)
    • Expect Black Ruby Barb to harass Cochu's Blue Tetra at times; give dense cover and watch them at feeding.
    • Your 75 L tank is below the ~100 L this pairing really wants — crowding raises aggression.
    • Keep Cochu's Blue Tetra in a shoal of 8+ 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 Cochu's Blue Tetra — plant heavily and break up sight lines.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Black Skirt Tetra in a shoal of 6+ or it gets stressed and nippy.
  • Desert Goby⚠️ With caution
    Semi-aggressive · 6 cm · Easy care · 18–28 °C (64–82 °F)
    • Desert Goby is semi-aggressive and may chase or nip the smaller Cochu's Blue Tetra — plant heavily and break up sight lines.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
  • Dwarf Chain Loach⚠️ With caution
    Peaceful · 6 cm · Medium care · 24–29 °C (75–84 °F)
    • Your 75 L tank is below the ~80 L this pairing really wants — crowding raises aggression.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Dwarf Chain Loach in a shoal of 6+ or it gets stressed and nippy.
  • Eastern Betta⚠️ With caution
    Semi-aggressive · 6 cm · Medium care · 24–28 °C (75–82 °F)
    • Expect Eastern Betta to harass Cochu's Blue Tetra at times; give dense cover and watch them at feeding.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
  • GloFish Tetra⚠️ With caution
    Semi-aggressive · 6 cm · Easy care · 21–28 °C (70–82 °F)
    • Expect GloFish Tetra to harass Cochu's Blue Tetra at times; give dense cover and watch them at feeding.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep GloFish Tetra 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 Cochu's Blue Tetra are close in size, but the semi-aggressive one tends to dominate — add cochu's blue tetra in a group to spread the pressure.
    • Your 75 L tank is below the ~80 L this pairing really wants — crowding raises aggression.
    • Keep Cochu's Blue Tetra in a shoal of 8+ 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 Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Morse Code Corydoras in a shoal of 6+ or it gets stressed and nippy.
  • Odessa Barb⚠️ With caution
    Semi-aggressive · 6 cm · Easy care · 20–26 °C (68–79 °F)
    • Odessa Barb is semi-aggressive and may chase or nip the smaller Cochu's Blue Tetra — plant heavily and break up sight lines.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Odessa Barb in a shoal of 6+ or it gets stressed and nippy.
  • Peaceful Betta⚠️ With caution
    Semi-aggressive · 6 cm · Medium care · 24–28 °C (75–82 °F)
    • Expect Peaceful Betta to harass Cochu's Blue Tetra at times; give dense cover and watch them at feeding.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
  • Silvertip Tetra⚠️ With caution
    Semi-aggressive · 5 cm · Easy care · 22–28 °C (72–82 °F)
    • Silvertip Tetra and Cochu's Blue Tetra are close in size, but the semi-aggressive one tends to dominate — add cochu's blue tetra in a group to spread the pressure.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
    • Keep Silvertip Tetra in a shoal of 6+ or it gets stressed and nippy.
  • Smaragd Betta⚠️ With caution
    Aggressive · 6 cm · Medium care · 23–28 °C (73–82 °F)
    • Expect Smaragd Betta to harass Cochu's Blue Tetra at times; give dense cover and watch them at feeding.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
  • Spotfin Betta⚠️ With caution
    Semi-aggressive · 5 cm · Medium care · 23–28 °C (73–82 °F)
    • Expect Spotfin Betta to harass Cochu's Blue Tetra at times; give dense cover and watch them at feeding.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
  • Striped Red-Eye Puffer⚠️ With caution
    Aggressive · 5 cm · Hard care · 24–28 °C (75–82 °F)
    • Expect Striped Red-Eye Puffer to harass Cochu's Blue Tetra at times; give dense cover and watch them at feeding.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
  • Wine Red Betta⚠️ With caution
    Aggressive · 5 cm · Medium care · 24–28 °C (75–82 °F)
    • Wine Red Betta is aggressive and may chase or nip the smaller Cochu's Blue Tetra — plant heavily and break up sight lines.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
  • Alligator Gar⛔ Not recommended
    Aggressive · 250 cm · Hard care · 24–28 °C (75–82 °F)
    • Cochu's Blue Tetra is bite-sized to a 250 cm predatory alligator gar — it will be eaten.
    • Alligator Gar is aggressive and may chase or nip the smaller Cochu's Blue Tetra — plant heavily and break up sight lines.
    • Your 75 L tank is below the ~3785 L this pairing really wants — crowding raises aggression.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
  • Clown Knifefish⛔ Not recommended
    Aggressive · 90 cm · Hard care · 24–28 °C (75–82 °F)
    • Size gap is too large (90 vs 5 cm): Clown Knifefish will treat Cochu's Blue Tetra as food.
    • Clown Knifefish clearly outsizes Cochu's Blue Tetra and is aggressive; risky unless the tank is big and well-planted.
    • Your 75 L tank is below the ~750 L this pairing really wants — crowding raises aggression.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
  • Fire Eel⛔ Not recommended
    Semi-aggressive · 100 cm · Medium care · 24–28 °C (75–82 °F)
    • Cochu's Blue Tetra is bite-sized to a 100 cm predatory fire eel — it will be eaten.
    • Fire Eel clearly outsizes Cochu's Blue Tetra and is semi-aggressive; risky unless the tank is big and well-planted.
    • Your 75 L tank is below the ~380 L this pairing really wants — crowding raises aggression.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
  • Koi⛔ Not recommended
    Peaceful · 90 cm · Medium care · 4–28 °C (39–82 °F)
    • Koi (90 cm) is big enough to swallow the 5 cm Cochu's Blue Tetra whole.
    • Your 75 L tank is below the ~3800 L this pairing really wants — crowding raises aggression.
    • Keep Cochu's Blue Tetra in a shoal of 8+ 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 5 cm): Redtail Catfish will treat Cochu's Blue Tetra as food.
    • Expect Redtail Catfish to harass Cochu's Blue Tetra at times; give dense cover and watch them at feeding.
    • Your 75 L tank is below the ~5700 L this pairing really wants — crowding raises aggression.
    • Keep Cochu's Blue Tetra in a shoal of 8+ 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 5 cm): Spotted Gar will treat Cochu's Blue Tetra as food.
    • Spotted Gar clearly outsizes Cochu's Blue Tetra and is aggressive; risky unless the tank is big and well-planted.
    • Your 75 L tank is below the ~600 L this pairing really wants — crowding raises aggression.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
  • Wels Catfish⛔ Not recommended
    Aggressive · 300 cm · Hard care · 15–25 °C (59–77 °F)
    • Wels Catfish (300 cm) is big enough to swallow the 5 cm Cochu's Blue Tetra whole.
    • Wels Catfish is aggressive and may chase or nip the smaller Cochu's Blue Tetra — plant heavily and break up sight lines.
    • Your 75 L tank is below the ~20000 L this pairing really wants — crowding raises aggression.
    • Keep Cochu's Blue Tetra in a shoal of 8+ or it gets stressed and nippy.
  • Wolf Cichlid⛔ Not recommended
    Aggressive · 72 cm · Hard care · 24–30 °C (75–86 °F)
    • Size gap is too large (72 vs 5 cm): Wolf Cichlid will treat Cochu's Blue Tetra as food.
    • Wolf Cichlid is aggressive and may chase or nip the smaller Cochu's Blue Tetra — plant heavily and break up sight lines.
    • Your 75 L tank is below the ~760 L this pairing really wants — crowding raises aggression.
    • Keep Cochu's Blue Tetra in a shoal of 8+ 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.

Setting up a cochu's blue tetra community tank

Give the group a stable, planted 75 L+ tank with a gentle filter, a reliable heater and plenty of cover — broken sight lines and hiding spots let mid-water and bottom dwellers keep out of each other's way. Cycle it fully and stock gradually.

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How to choose

How to choose the right tank mates for a cochu's blue tetra

As a peaceful species, cochu's blue tetra is easily bullied — favour other calm, non-nippy fish and steer clear of boisterous or aggressive tank mates. It mostly occupies the middle of the tank, so it pairs naturally with species that use the other levels.

Cochu's Blue Tetra grows to about 5 cm, so avoid tank mates small enough to be seen as food — as a rule of thumb, skip anything under roughly 3 cm. Match its water, too: aim for 22–28 °C (72–82 °F), pH 5.5–7.5 and 2–12 dGH. Fish needing very different conditions — coldwater species, or hard-water lovers against a soft-water fish — rarely thrive side by side.

Cochu's Blue Tetra is a shoaling fish — stock a group of 8+ of its own kind first, then build compatible tank mates around them. Whatever you add, introduce new fish slowly, watch for bullying in the first days, and have a backup plan if temperaments clash.

FAQ

Frequently asked questions

Can a cochu's blue tetra live with other fish?

Yes — with the right companions. Our checker finds 139 compatible freshwater species for cochu's blue tetra. Pick calm, similarly-sized fish that share its water needs and add them to a mature, well-planted tank.

What is the best tank mate for a cochu's blue tetra?

Easy, peaceful, similarly-sized species top the list — for example Ember Tetra, Neon Green Rasbora, Ramshorn Snail. Use the checker above to match against your own tank size.

What fish should you avoid keeping with a cochu's blue tetra?

Avoid Wels Catfish, Alligator Gar, Redtail Catfish and similar — usually a temperature, size or temperament clash. The full "avoid" list below gives the reason for each.

How big a tank do cochu's blue tetra tank mates need?

Start from Cochu's Blue Tetra's own minimum and scale up with every addition. The checker above defaults to a 75 L community tank and flags pairings that need more room — drag the slider to match your setup.

← Back to the full Cochu's Blue Tetra care guide