Green Severum Tank Mates

Green Severum is semi-aggressive, so its tank mates need choosing with care. Here are the 17 freshwater species that pair well with a green severum — plus the 59 to avoid — with a live checker you can tune to your own tank.

By The Aquarium DB Team • Updated June 7, 2026 • Full Green Severum care guide →
Best matches

The best tank mates for a green severum

  • Porthole Catfish ✅ Compatible
    Easy care · Peaceful · 10 cm · 22–28 °C (72–82 °F)
    Semi-aggressive + Peaceful, but with no direct clash here, and their water overlaps around 23–28 °C — no size, zone or temperament conflicts.
  • Upside-down Catfish ✅ Compatible
    Easy care · Peaceful · 10 cm · 22–26 °C (72–79 °F)
    Compatible on the things that matter: shared water near 23–26 °C, workable temperaments, and no predator-and-prey size gap.
  • Bristlenose Pleco ✅ Compatible
    Easy care · Peaceful · 12 cm · 23–30 °C (73–86 °F)
    Compatible on the things that matter: shared water near 23–29 °C, workable temperaments, and no predator-and-prey size gap.
  • Giant Kuhli Loach ✅ Compatible
    Easy care · Peaceful · 12 cm · 24–30 °C (75–86 °F)
    Semi-aggressive + Peaceful, but with no direct clash here, and their water overlaps around 24–29 °C — no size, zone or temperament conflicts.
  • Rubber Lip Pleco ✅ Compatible
    Easy care · Peaceful · 12 cm · 20–26 °C (68–79 °F)
    Semi-aggressive + Peaceful, but with no direct clash here, and their water overlaps around 23–26 °C — no size, zone or temperament conflicts.
  • Marbled Hoplo ✅ Compatible
    Easy care · Peaceful · 14 cm · 22–28 °C (72–82 °F)
    Semi-aggressive + Peaceful, but with no direct clash here, and their water overlaps around 23–28 °C — no size, zone or temperament conflicts.
  • Spotted Talking Catfish ✅ Compatible
    Easy care · Peaceful · 15 cm · 22–26 °C (72–79 °F)
    Semi-aggressive + Peaceful, but with no direct clash here, and their water overlaps around 23–26 °C — no size, zone or temperament conflicts.
  • Weather Loach ✅ Compatible
    Easy care · Peaceful · 25 cm · 5–24 °C (41–75 °F)
    Semi-aggressive + Peaceful, but with no direct clash here; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Clown Pleco ✅ Compatible
    Medium care · Peaceful · 9 cm · 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.
  • Leopard Frog Pleco ✅ Compatible
    Medium care · Peaceful · 9 cm · 25–30 °C (77–86 °F)
    Compatible on the things that matter: shared water near 25–29 °C, workable temperaments, and no predator-and-prey size gap.
  • Bearded Corydoras ✅ Compatible
    Medium care · Peaceful · 10 cm · 18–24 °C (64–75 °F)
    Semi-aggressive + Peaceful, but with no direct clash here; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Medusa Pleco ✅ Compatible
    Medium care · Peaceful · 12 cm · 26–30 °C (79–86 °F)
    Compatible on the things that matter: shared water near 26–29 °C, workable temperaments, and no predator-and-prey size gap.
  • Spotted Rubbernose Pleco ✅ Compatible
    Medium care · Peaceful · 12 cm · 20–26 °C (68–79 °F)
    Semi-aggressive + Peaceful, but with no direct clash here; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Striped Eel Loach ✅ Compatible
    Medium care · Peaceful · 12 cm · 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.
  • Banjo Catfish ✅ Compatible
    Medium care · Peaceful · 15 cm · 20–26 °C (68–79 °F)
    Semi-aggressive + Peaceful, but with no direct clash here; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Snowball Pleco ✅ Compatible
    Medium care · Peaceful · 16 cm · 24–30 °C (75–86 °F)
    Semi-aggressive + Peaceful, but with no direct clash here; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Zebra Pleco ✅ Compatible
    Hard care · Peaceful · 10 cm · 26–30 °C (79–86 °F)
    Semi-aggressive + Peaceful, but with no direct clash here, and their water overlaps around 26–29 °C — no size, zone or temperament conflicts.
With caution

Green Severum tank mates that can work with care

  • Adolf's Cory ⚠️ With caution
    Medium care · Peaceful · 5.5 cm · 22–26 °C (72–79 °F)
    Green Severum may bully the smaller Adolf's Cory, though its armour makes it a hard meal — give it caves and driftwood to retreat into.
  • 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)
    Both are a bit pushy (semi-aggressive + semi-aggressive) — workable only in a larger tank with cover and broken sight lines.
  • African Dwarf Frog ⚠️ With caution
    Medium care · Peaceful · 4 cm · 22–26 °C (72–79 °F)
    Watch for Green Severum picking off any african dwarf frog small enough to fit in its mouth.
  • Agassiz's Corydoras ⚠️ With caution
    Easy care · Peaceful · 6 cm · 22–28 °C (72–82 °F)
    Green Severum may bully the smaller Agassiz's Corydoras, though its armour makes it a hard meal — give it caves and driftwood to retreat into.
  • Agassiz's Dwarf Cichlid ⚠️ With caution
    Medium care · Semi-aggressive · 9 cm · 24–30 °C (75–86 °F)
    Green Severum and Agassiz's Dwarf Cichlid can both be territorial; doable with space and dense planting, but watch for chasing.
  • Altifrons Geophagus ⚠️ With caution
    Medium care · Semi-aggressive · 25 cm · 24–28 °C (75–82 °F)
    Green Severum and Altifrons Geophagus can both be territorial; doable with space and dense planting, but watch for chasing.
  • Amano Shrimp ⚠️ With caution
    Easy care · Peaceful · 5 cm · 18–28 °C (64–82 °F)
    Green Severum may eat Amano Shrimp or pick off its shrimplets — a densely planted tank with moss gives them a fighting chance.

+ 256 more “with caution” pairings — see the interactive checker above.

Avoid

Fish to avoid keeping with a green severum

  • Wels Catfish ⛔ Avoid
    Hard care · Aggressive · 300 cm · 15–25 °C (59–77 °F)
    Two assertive fish, one genuinely aggressive: Green Severum and Wels Catfish will hold territory and clash.
  • Alligator Gar ⛔ Avoid
    Hard care · Aggressive · 250 cm · 24–28 °C (75–82 °F)
    Two assertive fish, one genuinely aggressive: Green Severum and Alligator Gar will hold territory and clash.
  • Redtail Catfish ⛔ Avoid
    Hard care · Aggressive · 120 cm · 24–27 °C (75–81 °F)
    Two assertive fish, one genuinely aggressive: Green Severum and Redtail Catfish will hold territory and clash.
  • Fire Eel ⛔ Avoid
    Medium care · Semi-aggressive · 100 cm · 24–28 °C (75–82 °F)
    Fire Eel (100 cm) is big enough to swallow the 20 cm Green Severum whole.
  • Clown Knifefish ⛔ Avoid
    Hard care · Aggressive · 90 cm · 24–28 °C (75–82 °F)
    Green Severum and Clown Knifefish are both territorial and at least one is outright aggressive — expect serious fighting.
  • Koi ⛔ Avoid
    Medium care · Peaceful · 90 cm · 4–28 °C (39–82 °F)
    Size gap is too large (90 vs 20 cm): Koi will treat Green Severum as food.
  • Spotted Gar ⛔ Avoid
    Hard care · Aggressive · 90 cm · 18–26 °C (64–79 °F)
    Two assertive fish, one genuinely aggressive: Green Severum and Spotted Gar will hold territory and clash.
  • Wolf Cichlid ⛔ Avoid
    Hard care · Aggressive · 72 cm · 24–30 °C (75–86 °F)
    Green Severum and Wolf Cichlid are both territorial and at least one is outright aggressive — expect serious fighting.

+ 51 more to avoid — the checker above flags every one.

Interactive tool

Check any fish against a green severum

Dial in your exact tank size and filter by result — the checker scores every species in our database against a green severum, with the reasoning for each verdict.

Tank-mate checker

Will it live with a Green Severum?

We compare each fish against your green severum on temperament, size, water parameters and swimming zone. Set your tank size and filter the results.

  • Banjo Catfish✅ Compatible
    Peaceful · 15 cm · Medium care · 20–26 °C (68–79 °F)
    • Semi-aggressive + Peaceful, but with no direct clash here; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Bearded Corydoras✅ Compatible
    Peaceful · 10 cm · Medium care · 18–24 °C (64–75 °F)
    • Semi-aggressive + Peaceful, but with no direct clash here; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
    • Keep Bearded Corydoras in a shoal of 6+ or it gets stressed and nippy.
  • Bristlenose Pleco✅ Compatible
    Peaceful · 12 cm · Easy care · 23–30 °C (73–86 °F)
    • Compatible on the things that matter: shared water near 23–29 °C, workable temperaments, and no predator-and-prey size gap.
  • Clown Pleco✅ Compatible
    Peaceful · 9 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.
  • Giant Kuhli Loach✅ Compatible
    Peaceful · 12 cm · Easy care · 24–30 °C (75–86 °F)
    • Semi-aggressive + Peaceful, but with no direct clash here, and their water overlaps around 24–29 °C — no size, zone or temperament conflicts.
  • Leopard Frog Pleco✅ Compatible
    Peaceful · 9 cm · Medium care · 25–30 °C (77–86 °F)
    • Compatible on the things that matter: shared water near 25–29 °C, workable temperaments, and no predator-and-prey size gap.
  • Marbled Hoplo✅ Compatible
    Peaceful · 14 cm · Easy care · 22–28 °C (72–82 °F)
    • Semi-aggressive + Peaceful, but with no direct clash here, and their water overlaps around 23–28 °C — no size, zone or temperament conflicts.
  • Medusa Pleco✅ Compatible
    Peaceful · 12 cm · Medium care · 26–30 °C (79–86 °F)
    • Compatible on the things that matter: shared water near 26–29 °C, workable temperaments, and no predator-and-prey size gap.
  • Porthole Catfish✅ Compatible
    Peaceful · 10 cm · Easy care · 22–28 °C (72–82 °F)
    • Semi-aggressive + Peaceful, but with no direct clash here, and their water overlaps around 23–28 °C — no size, zone or temperament conflicts.
  • Rubber Lip Pleco✅ Compatible
    Peaceful · 12 cm · Easy care · 20–26 °C (68–79 °F)
    • Semi-aggressive + Peaceful, but with no direct clash here, and their water overlaps around 23–26 °C — no size, zone or temperament conflicts.
  • Snowball Pleco✅ Compatible
    Peaceful · 16 cm · Medium care · 24–30 °C (75–86 °F)
    • Semi-aggressive + Peaceful, but with no direct clash here; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Spotted Rubbernose Pleco✅ Compatible
    Peaceful · 12 cm · Medium care · 20–26 °C (68–79 °F)
    • Semi-aggressive + Peaceful, but with no direct clash here; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Spotted Talking Catfish✅ Compatible
    Peaceful · 15 cm · Easy care · 22–26 °C (72–79 °F)
    • Semi-aggressive + Peaceful, but with no direct clash here, and their water overlaps around 23–26 °C — no size, zone or temperament conflicts.
  • Striped Eel Loach✅ Compatible
    Peaceful · 12 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.
  • Upside-down Catfish✅ Compatible
    Peaceful · 10 cm · Easy care · 22–26 °C (72–79 °F)
    • Compatible on the things that matter: shared water near 23–26 °C, workable temperaments, and no predator-and-prey size gap.
  • Weather Loach✅ Compatible
    Peaceful · 25 cm · Easy care · 5–24 °C (41–75 °F)
    • Semi-aggressive + Peaceful, but with no direct clash here; temperature, pH and hardness ranges all overlap and neither outsizes the other enough to be a threat.
  • Zebra Pleco✅ Compatible
    Peaceful · 10 cm · Hard care · 26–30 °C (79–86 °F)
    • Semi-aggressive + Peaceful, but with no direct clash here, and their water overlaps around 26–29 °C — no size, zone or temperament conflicts.
  • Altifrons Geophagus⚠️ With caution
    Semi-aggressive · 25 cm · Medium care · 24–28 °C (75–82 °F)
    • Green Severum and Altifrons Geophagus can both be territorial; doable with space and dense planting, but watch for chasing.
    • Your 208 L tank is below the ~378 L this pairing really wants — crowding raises aggression.
    • Keep Altifrons Geophagus in a shoal of 6+ or it gets stressed and nippy.
  • Angelicus Synodontis⚠️ With caution
    Semi-aggressive · 25 cm · Medium care · 23–27 °C (73–81 °F)
    • Green Severum and Angelicus Synodontis can both be territorial; doable with space and dense planting, but watch for chasing.
  • Blood Parrot Cichlid⚠️ With caution
    Semi-aggressive · 20 cm · Medium care · 24–28 °C (75–82 °F)
    • Green Severum and Blood Parrot Cichlid can both be territorial; doable with space and dense planting, but watch for chasing.
  • Discus⚠️ With caution
    Peaceful · 20 cm · Hard care · 28–31 °C (82–88 °F)
    • Green Severum and Discus are close in size, but the semi-aggressive one tends to dominate — add discus in a group to spread the pressure.
    • Keep Discus in a shoal of 6+ or it gets stressed and nippy.
  • Electric Blue Acara⚠️ With caution
    Semi-aggressive · 16 cm · Medium care · 22–28 °C (72–82 °F)
    • Both are a bit pushy (semi-aggressive + semi-aggressive) — workable only in a larger tank with cover and broken sight lines.
  • Electric Blue Hap⚠️ With caution
    Semi-aggressive · 20 cm · Medium care · 24–28 °C (75–82 °F)
    • pH preferences only just meet (Green Severum 5.5–7.5 vs Electric Blue Hap 7.8–8.5) — target the overlap and acclimate slowly.
    • Green Severum and Electric Blue Hap can both be territorial; doable with space and dense planting, but watch for chasing.
    • Your 208 L tank is below the ~250 L this pairing really wants — crowding raises aggression.
  • Emperor Peacock Cichlid⚠️ With caution
    Semi-aggressive · 16 cm · Medium care · 24–28 °C (75–82 °F)
    • pH preferences only just meet (Green Severum 5.5–7.5 vs Emperor Peacock Cichlid 7.6–8.6) — target the overlap and acclimate slowly.
    • Green Severum and Emperor Peacock Cichlid can both be territorial; doable with space and dense planting, but watch for chasing.
    • Your 208 L tank is below the ~210 L this pairing really wants — crowding raises aggression.
  • Fire Blue Empress Cichlid⚠️ With caution
    Semi-aggressive · 18 cm · Medium care · 24–28 °C (75–82 °F)
    • Green Severum and Fire Blue Empress Cichlid can both be territorial; doable with space and dense planting, but watch for chasing.
    • Your 208 L tank is below the ~400 L this pairing really wants — crowding raises aggression.
  • Galaxy Pleco⚠️ With caution
    Semi-aggressive · 25 cm · Medium care · 22–26 °C (72–79 °F)
    • Green Severum and Galaxy Pleco can both be territorial; doable with space and dense planting, but watch for chasing.
  • Goldie Pleco⚠️ With caution
    Semi-aggressive · 20 cm · Medium care · 24–29 °C (75–84 °F)
    • Green Severum and Goldie Pleco can both be territorial; doable with space and dense planting, but watch for chasing.
  • Guyana Flag Cichlid⚠️ With caution
    Semi-aggressive · 18 cm · Medium care · 24–30 °C (75–86 °F)
    • Both are a bit pushy (semi-aggressive + semi-aggressive) — workable only in a larger tank with cover and broken sight lines.
  • Honeycomb Pleco⚠️ With caution
    Semi-aggressive · 21 cm · Medium care · 24–29 °C (75–84 °F)
    • Green Severum and Honeycomb Pleco can both be territorial; doable with space and dense planting, but watch for chasing.
    • Your 208 L tank is below the ~280 L this pairing really wants — crowding raises aggression.
  • Platinum Acara⚠️ With caution
    Semi-aggressive · 20 cm · Medium care · 23–28 °C (73–82 °F)
    • Both are a bit pushy (semi-aggressive + semi-aggressive) — workable only in a larger tank with cover and broken sight lines.
  • Spanner Barb⚠️ With caution
    Semi-aggressive · 18 cm · Medium care · 23–29 °C (73–84 °F)
    • Both are a bit pushy (semi-aggressive + semi-aggressive) — workable only in a larger tank with cover and broken sight lines.
    • Spanner Barb is a notorious fin-nipper — even though Green Severum is larger, an active shoal will harass its trailing fins. Only safe in a full group of 6+ with plenty of cover.
    • Keep Spanner Barb in a shoal of 6+ or it gets stressed and nippy.
  • Striped Raphael Catfish⚠️ With caution
    Semi-aggressive · 20 cm · Medium care · 24–28 °C (75–82 °F)
    • Green Severum and Striped Raphael Catfish can both be territorial; doable with space and dense planting, but watch for chasing.
  • Tiger Loach⚠️ With caution
    Semi-aggressive · 20 cm · Medium care · 23–27 °C (73–81 °F)
    • Both are a bit pushy (semi-aggressive + semi-aggressive) — workable only in a larger tank with cover and broken sight lines.
  • Alligator Gar⛔ Not recommended
    Aggressive · 250 cm · Hard care · 24–28 °C (75–82 °F)
    • Two assertive fish, one genuinely aggressive: Green Severum and Alligator Gar will hold territory and clash.
    • Alligator Gar (250 cm) is big enough to swallow the 20 cm Green Severum whole.
    • Your 208 L tank is below the ~3785 L this pairing really wants — crowding raises aggression.
  • Clown Knifefish⛔ Not recommended
    Aggressive · 90 cm · Hard care · 24–28 °C (75–82 °F)
    • Green Severum and Clown Knifefish are both territorial and at least one is outright aggressive — expect serious fighting.
    • Size gap is too large (90 vs 20 cm): Clown Knifefish will treat Green Severum as food.
    • Your 208 L tank is below the ~750 L this pairing really wants — crowding raises aggression.
  • Fire Eel⛔ Not recommended
    Semi-aggressive · 100 cm · Medium care · 24–28 °C (75–82 °F)
    • Fire Eel (100 cm) is big enough to swallow the 20 cm Green Severum whole.
    • Both are a bit pushy (semi-aggressive + semi-aggressive) — workable only in a larger tank with cover and broken sight lines.
    • Your 208 L tank is below the ~380 L this pairing really wants — crowding raises aggression.
  • Koi⛔ Not recommended
    Peaceful · 90 cm · Medium care · 4–28 °C (39–82 °F)
    • Size gap is too large (90 vs 20 cm): Koi will treat Green Severum as food.
    • Your 208 L tank is below the ~3800 L this pairing really wants — crowding raises aggression.
  • Redtail Catfish⛔ Not recommended
    Aggressive · 120 cm · Hard care · 24–27 °C (75–81 °F)
    • Two assertive fish, one genuinely aggressive: Green Severum and Redtail Catfish will hold territory and clash.
    • Size gap is too large (120 vs 20 cm): Redtail Catfish will treat Green Severum as food.
    • Your 208 L tank is below the ~5700 L this pairing really wants — crowding raises aggression.
  • Spotted Gar⛔ Not recommended
    Aggressive · 90 cm · Hard care · 18–26 °C (64–79 °F)
    • Two assertive fish, one genuinely aggressive: Green Severum and Spotted Gar will hold territory and clash.
    • Size gap is too large (90 vs 20 cm): Spotted Gar will treat Green Severum as food.
    • Your 208 L tank is below the ~600 L this pairing really wants — crowding raises aggression.
  • Wels Catfish⛔ Not recommended
    Aggressive · 300 cm · Hard care · 15–25 °C (59–77 °F)
    • Two assertive fish, one genuinely aggressive: Green Severum and Wels Catfish will hold territory and clash.
    • Size gap is too large (300 vs 20 cm): Wels Catfish will treat Green Severum as food.
    • Your 208 L tank is below the ~20000 L this pairing really wants — crowding raises aggression.
  • Wolf Cichlid⛔ Not recommended
    Aggressive · 72 cm · Hard care · 24–30 °C (75–86 °F)
    • Green Severum and Wolf Cichlid are both territorial and at least one is outright aggressive — expect serious fighting.
    • Green Severum is bite-sized to a 72 cm predatory wolf cichlid — it will be eaten.
    • Your 208 L tank is below the ~760 L this pairing really wants — crowding raises aggression.

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 green severum community tank

Give the group a stable, planted 208 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.

As an Amazon Associate we earn from qualifying purchases — buying through these links costs you nothing extra.

How to choose

How to choose the right tank mates for a green severum

Being semi-aggressive, green severum can nip or harass smaller, slower or long-finned fish — give it space, broken sight-lines and similarly robust companions. It mostly occupies the middle of the tank, so it pairs naturally with species that use the other levels.

Green Severum grows to about 20 cm, so avoid tank mates small enough to be seen as food — as a rule of thumb, skip anything under roughly 10 cm. Match its water, too: aim for 23–29 °C (73–84 °F), pH 5.5–7.5 and 1–10 dGH. Fish needing very different conditions — coldwater species, or hard-water lovers against a soft-water fish — rarely thrive side by side.

Green Severum doesn't need its own kind to feel secure; think twice before keeping more than one if it is territorial. 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 green severum live with other fish?

Yes — with the right companions. Our checker finds 17 compatible freshwater species for green severum. 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 green severum?

Easy, peaceful, similarly-sized species top the list — for example Porthole Catfish, Upside-down Catfish, Bristlenose Pleco. Use the checker above to match against your own tank size.

What fish should you avoid keeping with a green severum?

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 green severum tank mates need?

Start from Green Severum's own minimum and scale up with every addition. The checker above defaults to a 208 L community tank and flags pairings that need more room — drag the slider to match your setup.

← Back to the full Green Severum care guide