Photo: Marrabbio2 (CC BY-SA 3.0) — via Wikimedia Commons
Colombian Tetra (Hyphessobrycon columbianus)
A bold, iridescent tetra with electric-blue flanks and blood-red fins — one of the most visually striking characins in the freshwater hobby.
Will it live with a Colombian Tetra?
We compare each fish against your colombian tetra on temperament, size, water parameters and swimming zone. Set your tank size and filter the results.
- Adolf's Cory✅ CompatiblePeaceful · 5.5 cm · Medium care · 22–26 °C (72–79 °F)
- Semi-aggressive + Peaceful, but with no direct clash here, and their water overlaps around 24–26 °C — no size, zone or temperament conflicts.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Adolf's Cory in a shoal of 6+ or it gets stressed and nippy.
- Agassiz's Corydoras✅ CompatiblePeaceful · 6 cm · Easy care · 22–28 °C (72–82 °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 Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Agassiz's Corydoras in a shoal of 6+ or it gets stressed and nippy.
- Blood Red Tiger Pleco✅ CompatiblePeaceful · 6 cm · Medium care · 24–29 °C (75–84 °F)
- Semi-aggressive + Peaceful, but with no direct clash here, and their water overlaps around 24–28 °C — no size, zone or temperament conflicts.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Bright Diamond Tetra✅ CompatiblePeaceful · 7 cm · Hard care · 24–28 °C (75–82 °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.
- Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Bright Diamond Tetra in a shoal of 8+ or it gets stressed and nippy.
- Butterfly Hillstream Loach✅ CompatiblePeaceful · 6 cm · Hard care · 18–24 °C (64–75 °F)
- Semi-aggressive + Peaceful, but with no direct clash here, and their water overlaps around 24–24 °C — no size, zone or temperament conflicts.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Celebes Rainbowfish✅ CompatiblePeaceful · 7 cm · Medium care · 22–28 °C (72–82 °F)
- Semi-aggressive + Peaceful, but with no direct clash here, 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 Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Celebes Rainbowfish in a shoal of 6+ or it gets stressed and nippy.
- Corydoras Catfish✅ CompatiblePeaceful · 6.5 cm · Easy care · 22–26 °C (72–79 °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.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Corydoras Catfish in a shoal of 6+ or it gets stressed and nippy.
- Costa's Tetra✅ CompatiblePeaceful · 7 cm · Easy care · 22–28 °C (72–82 °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 Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Costa's Tetra in a shoal of 6+ or it gets stressed and nippy.
- Duplicareus Corydoras✅ CompatiblePeaceful · 5.5 cm · Medium care · 23–27 °C (73–81 °F)
- Compatible on the things that matter: shared water near 24–27 °C, workable temperaments, and no predator-and-prey size gap.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Duplicareus Corydoras in a shoal of 6+ or it gets stressed and nippy.
- Dwarf Chain Loach✅ CompatiblePeaceful · 6 cm · Medium care · 24–29 °C (75–84 °F)
- Semi-aggressive + Peaceful, but with no direct clash here, and their water overlaps around 24–28 °C — no size, zone or temperament conflicts.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Dwarf Chain Loach in a shoal of 6+ or it gets stressed and nippy.
- Elegant Cory✅ CompatiblePeaceful · 6 cm · Easy care · 22–28 °C (72–82 °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 Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Elegant Cory in a shoal of 6+ or it gets stressed and nippy.
- False Julii Corydoras✅ CompatiblePeaceful · 6 cm · Easy care · 22–26 °C (72–79 °F)
- Compatible on the things that matter: shared water near 24–26 °C, workable temperaments, and no predator-and-prey size gap.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep False Julii Corydoras in a shoal of 6+ or it gets stressed and nippy.
- German Blue Ram✅ CompatiblePeaceful · 6 cm · Hard care · 27–30 °C (81–86 °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.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Gold Barb✅ CompatiblePeaceful · 7.5 cm · Easy care · 18–26 °C (64–79 °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.
- Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Gold Barb in a shoal of 6+ or it gets stressed and nippy.
- Hillstream Loach✅ CompatiblePeaceful · 6 cm · Hard care · 20–24 °C (68–75 °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 Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Melon Barb✅ CompatiblePeaceful · 7 cm · Easy care · 22–28 °C (72–82 °F)
- Semi-aggressive + Peaceful, but with no direct clash here, 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 Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Melon Barb in a shoal of 8+ or it gets stressed and nippy.
- Peacock Gudgeon✅ CompatiblePeaceful · 7 cm · Medium care · 22–28 °C (72–82 °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 Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Peppered Corydoras✅ CompatiblePeaceful · 7 cm · Easy care · 18–26 °C (64–79 °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.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Peppered Corydoras in a shoal of 6+ or it gets stressed and nippy.
- Rio Negro Checkerboard Cichlid✅ CompatiblePeaceful · 7 cm · Hard care · 24–29 °C (75–84 °F)
- Semi-aggressive + Peaceful, but with no direct clash here, and their water overlaps around 24–28 °C — no size, zone or temperament conflicts.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Rounded Filament Barb✅ CompatiblePeaceful · 7 cm · Medium care · 22–27 °C (72–81 °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.
- Both favour the middle of the tank — offer enough cover so they aren't always in each other's space.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Rounded Filament Barb in a shoal of 6+ or it gets stressed and nippy.
- Slate Corydoras✅ CompatiblePeaceful · 6 cm · Medium care · 23–28 °C (73–82 °F)
- Compatible on the things that matter: shared water near 24–28 °C, workable temperaments, and no predator-and-prey size gap.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Slate Corydoras in a shoal of 6+ or it gets stressed and nippy.
- Spotfin Corydoras✅ CompatiblePeaceful · 6.5 cm · Easy care · 22–26 °C (72–79 °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.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Spotfin Corydoras in a shoal of 6+ or it gets stressed and nippy.
- Spotted Corydoras✅ CompatiblePeaceful · 7 cm · Easy care · 22–27 °C (72–81 °F)
- Compatible on the things that matter: shared water near 24–27 °C, workable temperaments, and no predator-and-prey size gap.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Spotted Corydoras in a shoal of 6+ or it gets stressed and nippy.
- Sterbai Corydoras✅ CompatiblePeaceful · 6.5 cm · Medium care · 24–30 °C (75–86 °F)
- Compatible on the things that matter: shared water near 24–28 °C, workable temperaments, and no predator-and-prey size gap.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Sterbai Corydoras in a shoal of 6+ or it gets stressed and nippy.
- Ash Lipped Apisto⚠️ With cautionSemi-aggressive · 7 cm · Hard care · 24–29 °C (75–84 °F)
- Colombian Tetra and Ash Lipped Apisto can both be territorial; doable with space and dense planting, but watch for chasing.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Banded Dwarf Cichlid⚠️ With cautionSemi-aggressive · 7 cm · Medium care · 24–30 °C (75–86 °F)
- Colombian Tetra and Banded Dwarf Cichlid can both be territorial; doable with space and dense planting, but watch for chasing.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Betta⚠️ With cautionSemi-aggressive · 6.5 cm · Easy care · 24–28 °C (75–82 °F)
- Colombian Tetra and Betta can both be territorial; doable with space and dense planting, but watch for chasing.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Black Ruby Barb⚠️ With cautionSemi-aggressive · 6 cm · Easy care · 22–26 °C (72–79 °F)
- Colombian Tetra and Black Ruby Barb can both be territorial; doable with space and dense planting, but watch for chasing.
- Keep Colombian Tetra 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 cautionSemi-aggressive · 6 cm · Easy care · 20–26 °C (68–79 °F)
- Colombian Tetra and Black Skirt Tetra can both be territorial; doable with space and dense planting, but watch for chasing.
- Keep Colombian Tetra 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.
- Blackline Rasbora⚠️ With cautionPeaceful · 6 cm · Easy care · 22–28 °C (72–82 °F)
- Expect Colombian Tetra to harass Blackline Rasbora at times; give dense cover and watch them at feeding.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Blackline Rasbora in a shoal of 6+ or it gets stressed and nippy.
- Bleeding Heart Tetra⚠️ With cautionSemi-aggressive · 7 cm · Medium care · 23–28 °C (73–82 °F)
- Colombian Tetra and Bleeding Heart Tetra can both be territorial; doable with space and dense planting, but watch for chasing.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Bleeding Heart Tetra in a shoal of 6+ or it gets stressed and nippy.
- Buenos Aires Tetra⚠️ With cautionSemi-aggressive · 7 cm · Easy care · 18–26 °C (64–79 °F)
- Colombian Tetra and Buenos Aires Tetra can both be territorial; doable with space and dense planting, but watch for chasing.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Buenos Aires Tetra in a shoal of 6+ or it gets stressed and nippy.
- Croaking Gourami⚠️ With cautionPeaceful · 7 cm · Easy care · 24–28 °C (75–82 °F)
- Colombian Tetra is a notorious fin-nipper — even though Croaking Gourami is larger, an active shoal will harass its trailing fins. Only safe in a full group of 6+ with plenty of cover.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Desert Goby⚠️ With cautionSemi-aggressive · 6 cm · Easy care · 18–28 °C (64–82 °F)
- Both are a bit pushy (semi-aggressive + semi-aggressive) — workable only in a larger tank with cover and broken sight lines.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Diamond Tetra⚠️ With cautionPeaceful · 6 cm · Easy care · 22–28 °C (72–82 °F)
- Colombian Tetra is semi-aggressive and may chase or nip the smaller Diamond Tetra — plant heavily and break up sight lines.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Diamond Tetra in a shoal of 6+ or it gets stressed and nippy.
- Hongsloi Dwarf Cichlid⚠️ With cautionSemi-aggressive · 7 cm · Medium care · 24–29 °C (75–84 °F)
- Both are a bit pushy (semi-aggressive + semi-aggressive) — workable only in a larger tank with cover and broken sight lines.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Roundtail Paradise Fish⚠️ With cautionSemi-aggressive · 7 cm · Easy care · 10–26 °C (50–79 °F)
- Both are a bit pushy (semi-aggressive + semi-aggressive) — workable only in a larger tank with cover and broken sight lines.
- Colombian Tetra is a notorious fin-nipper — even though Roundtail Paradise Fish is larger, an active shoal will harass its trailing fins. Only safe in a full group of 6+ with plenty of cover.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Sumo Loach⚠️ With cautionSemi-aggressive · 7 cm · Medium care · 22–26 °C (72–79 °F)
- Colombian Tetra and Sumo Loach can both be territorial; doable with space and dense planting, but watch for chasing.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Tiger Barb⚠️ With cautionSemi-aggressive · 7 cm · Easy 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.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Keep Tiger Barb in a shoal of 6+ or it gets stressed and nippy.
- Umbrella Dwarf Cichlid⚠️ With cautionSemi-aggressive · 7 cm · Medium care · 20–26 °C (68–79 °F)
- Colombian Tetra and Umbrella Dwarf Cichlid can both be territorial; doable with space and dense planting, but watch for chasing.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Alligator Gar⛔ Not recommendedAggressive · 250 cm · Hard care · 24–28 °C (75–82 °F)
- Two assertive fish, one genuinely aggressive: Colombian Tetra and Alligator Gar will hold territory and clash.
- Colombian Tetra is bite-sized to a 250 cm predatory alligator gar — it will be eaten.
- Alligator Gar is slow and long-finned; a busy colombian tetra shoal tends to nip at it. Keep colombian tetra in a proper group of 6+ and watch them closely.
- Your 114 L tank is below the ~3785 L this pairing really wants — crowding raises aggression.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Clown Knifefish⛔ Not recommendedAggressive · 90 cm · Hard care · 24–28 °C (75–82 °F)
- Colombian Tetra and Clown Knifefish are both territorial and at least one is outright aggressive — expect serious fighting.
- Size gap is too large (90 vs 6.5 cm): Clown Knifefish will treat Colombian Tetra as food.
- Your 114 L tank is below the ~750 L this pairing really wants — crowding raises aggression.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Fire Eel⛔ Not recommendedSemi-aggressive · 100 cm · Medium care · 24–28 °C (75–82 °F)
- Fire Eel (100 cm) is big enough to swallow the 6.5 cm Colombian Tetra whole.
- Both are a bit pushy (semi-aggressive + semi-aggressive) — workable only in a larger tank with cover and broken sight lines.
- Your 114 L tank is below the ~380 L this pairing really wants — crowding raises aggression.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Koi⛔ Not recommendedPeaceful · 90 cm · Medium care · 4–28 °C (39–82 °F)
- Koi (90 cm) is big enough to swallow the 6.5 cm Colombian Tetra whole.
- Colombian Tetra is a notorious fin-nipper — even though Koi is larger, an active shoal will harass its trailing fins. Only safe in a full group of 6+ with plenty of cover.
- Your 114 L tank is below the ~3800 L this pairing really wants — crowding raises aggression.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Redtail Catfish⛔ Not recommendedAggressive · 120 cm · Hard care · 24–27 °C (75–81 °F)
- Two assertive fish, one genuinely aggressive: Colombian Tetra and Redtail Catfish will hold territory and clash.
- Size gap is too large (120 vs 6.5 cm): Redtail Catfish will treat Colombian Tetra as food.
- Your 114 L tank is below the ~5700 L this pairing really wants — crowding raises aggression.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Spotted Gar⛔ Not recommendedAggressive · 90 cm · Hard care · 18–26 °C (64–79 °F)
- Two assertive fish, one genuinely aggressive: Colombian Tetra and Spotted Gar will hold territory and clash.
- Spotted Gar (90 cm) is big enough to swallow the 6.5 cm Colombian Tetra whole.
- Spotted Gar is slow and long-finned; a busy colombian tetra shoal tends to nip at it. Keep colombian tetra in a proper group of 6+ and watch them closely.
- Your 114 L tank is below the ~600 L this pairing really wants — crowding raises aggression.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Wels Catfish⛔ Not recommendedAggressive · 300 cm · Hard care · 15–25 °C (59–77 °F)
- Two assertive fish, one genuinely aggressive: Colombian Tetra and Wels Catfish will hold territory and clash.
- Wels Catfish (300 cm) is big enough to swallow the 6.5 cm Colombian Tetra whole.
- Your 114 L tank is below the ~20000 L this pairing really wants — crowding raises aggression.
- Keep Colombian Tetra in a shoal of 6+ or it gets stressed and nippy.
- Wolf Cichlid⛔ Not recommendedAggressive · 72 cm · Hard care · 24–30 °C (75–86 °F)
- Colombian Tetra and Wolf Cichlid are both territorial and at least one is outright aggressive — expect serious fighting.
- Wolf Cichlid (72 cm) is big enough to swallow the 6.5 cm Colombian Tetra whole.
- Colombian Tetra is a notorious fin-nipper — even though Wolf Cichlid is larger, an active shoal will harass its trailing fins. Only safe in a full group of 6+ with plenty of cover.
- Your 114 L tank is below the ~760 L this pairing really wants — crowding raises aggression.
- Keep Colombian Tetra 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.
Colombian Tetra care specs
- Care level
- Easy
- Breeding
- Medium
- Max size
- 6.5 cm (2.6 in)
- Min tank size
- 114 L (30.1 gal)
- Temperature
- 24–28 °C (75–82 °F)
- pH
- 6–7.5
- Hardness
- 3–15 dGH
- Lifespan
- 3–5 years
- Diet
- Omnivore
- Swim level
- Middle
- Group size
- 6+ (shoaling)
- Family
- Characidae
- Origin
- Northwestern Colombia — Acandí River drainage (South America)
What is a Colombian Tetra?
The Colombian tetra (Hyphessobrycon columbianus), also sold as the Red & Blue Colombian Tetra or Blue-Red Colombian Tetra, is a large, robustly built characin native to the Acandí River drainage in northwestern Colombia. It reaches around 6.5 cm (2.5 in) — significantly bigger than the neon or cardinal tetra — and carries a striking two-tone livery: silver-grey flanks with a vivid turquoise-blue iridescent sheen running from the lateral line upward, set against fins tipped in deep red with white edges. That combination makes it one of the most visually arresting mid-water fish available in the freshwater hobby.
Despite its imposing good looks, the Colombian tetra is a hardy, adaptable fish that tolerates a broad range of water conditions and readily accepts most aquarium foods. Its main quirk is a tendency to nip at slow or long-finned tank-mates — a trait easily managed by keeping a proper-sized school and choosing companions thoughtfully.
Where do Colombian Tetras come from?
Hyphessobrycon columbianus is native to the Acandí River drainage in the Chocó biogeographic region of northwestern Colombia, near the border with Panama. The rivers there drain into the Caribbean and are typically warm, moderately soft, and shaded by dense tropical forest canopy. Current carries leaves and organic debris into the water, staining it lightly and providing tannins that keep pH mildly acidic.
This origin explains a lot about ideal captive conditions: the species expects warmth, moderate movement, low to moderate hardness, and plenty of broken light and cover. Though captive-bred stock is widely available and far more adaptable than wild-caught fish, replicating the general feel of that Neotropical habitat — soft substrate, plants, some wood or leaf litter — yields noticeably better colour and behaviour.
What Tank Size and Setup Do Colombian Tetras Need?
The minimum recommended tank size is 114 litres (30 gallons), and for a group of ten or more — which is ideal — a 150–200 L (40–55 gal) tank is more practical. Colombian tetras are active, mid-water swimmers that need horizontal length to express natural schooling behaviour; a long tank footprint matters more than height.
For substrate, a dark, fine-grained sand or gravel helps the fish feel secure and makes their iridescent blue pop visually. Plant the sides and back of the tank — dense vegetation gives the school a sense of shelter — and leave a clear, open swimming lane through the centre. Driftwood and dried leaf litter contribute tannins and replicate the natural habitat. Lighting can be moderate; very bright, open setups tend to wash out the blue iridescence and make the fish skittish. A gentle-to-moderate filter flow is appreciated; strong surface agitation is not necessary but tolerated.
What Water Parameters Do Colombian Tetras Need?
- Temperature: 24–28 °C (75–82 °F)
- pH: 6.0–7.5
- Hardness: 3–15 dGH
Colombian tetras are among the more forgiving Hyphessobrycon species when it comes to water chemistry. They do well anywhere in that pH and hardness range, making them compatible with many general community tanks running neutral, moderately hard tap water. That said, stability always trumps target values — rapid parameter swings stress them far more than a pH of 7.2 versus 6.8 ever would. Cycle the tank fully before adding fish, keep up weekly partial water changes of around 25–30 %, and monitor temperature consistently, as drops below 24 °C (75 °F) are the most common stressor in cooler climates.
What Do Colombian Tetras Eat?
Colombian tetras are omnivores with an opportunistic feeding style. In the wild they take small invertebrates, insects and plant material; in the aquarium they accept virtually everything offered. A quality flake or micro-pellet makes a solid staple. Rotating in frozen or live foods — brine shrimp, daphnia, bloodworms, and mosquito larvae — keeps condition and fin colour sharp, and provides the protein boost that brings out the deep red in the fins particularly well.
Feed small amounts once or twice daily, only what the school clears in two to three minutes. Because these are active fish in a group, competition at feeding time is healthy, but watch for shyer individuals getting crowded out. Sinking wafers or slow-sinking pellets can be scattered to spread feeding across the tank.
How Do Colombian Tetras Behave — and What Fish Can Live with Them?
Colombian tetras are semi-aggressive shoaling fish. Within their own group they are energetic and cohesive; the school forms, breaks, and reforms constantly during the day. The aggression issue is specifically fin-nipping directed at slow-moving, long-finned tank-mates — bettas, fancy guppies, angelfish, and similar fish are poor companions, especially in smaller tanks.
The single most effective management tool is group size: keep at least six, ideally ten or more. In a proper-sized school, intra-group activity consumes the fish’s competitive energy, and nipping at other species drops substantially. Good companions are robust, active community fish of similar size: other larger tetras (such as Buenos Aires or black skirt tetras), medium-sized barbs, larger rasboras, corydoras catfish, and peaceful dwarf cichlids like the Bolivian ram or German blue ram, which share the same temperature and pH range.
For a full breakdown of suitable pairings, see Colombian Tetra tank mates.
How Do You Tell a Male from a Female Colombian Tetra?
Sexual dimorphism is present but subtle in this species. Males are typically slimmer in the body and display more intense red colouration in the dorsal, anal and caudal fins. Females are slightly larger overall and become noticeably fuller and rounder in the belly region when gravid (carrying eggs), which is the clearest indicator when a breeding group is well-conditioned. Outside of breeding condition the differences are modest, and young fish are difficult to sex reliably until they reach adult size around 5–6 cm (2–2.3 in).
How Do Colombian Tetras Breed?
Colombian tetras are egg scatterers and do not provide parental care. Breeding is achievable in the home aquarium but requires preparation, which earns it a medium difficulty rating.
Condition a small group of adults — ideally two or three pairs — in a separate breeding tank of around 40–60 L (10–16 gal) with very soft, slightly acidic water (pH 6.0–6.5, hardness 2–5 dGH) and a water temperature at the warmer end of the range, around 27–28 °C (81–82 °F). Add a spawning mop or fine-leaved plants like java moss to catch the eggs, and dim the lighting. Feed heavily with live or frozen foods for one to two weeks to bring the fish into breeding condition.
Spawning typically occurs in the early morning. The pair or group will scatter adhesive eggs among the plants or mop. Remove the adults promptly after spawning — they will eat the eggs. Eggs hatch in roughly 24–36 hours; free-swimming fry appear two to three days after hatching and accept infusoria or commercial fry foods initially, graduating to baby brine shrimp as they grow.
What Diseases Commonly Affect Colombian Tetras?
Colombian tetras are generally robust, but they are susceptible to the same conditions that affect most tropical community fish. Ich (Ichthyophthirius multifiliis) — small white spots across the body and fins — is the most frequently encountered, usually triggered by a temperature drop or the stress of new introductions. Fin rot (ragged, receding fin margins) is almost always a water-quality problem. Velvet (a fine, gold-dusted sheen) and neon tetra disease (pale, wasting patches — rare but present in the tetra family) occasionally appear.
Prevention is straightforward: maintain stable temperature, perform regular water changes, quarantine all new fish for two to four weeks before introducing them to the display tank, and avoid overstocking. A healthy school of Colombian tetras, properly fed and kept in clean water, rarely falls ill.
Health note: disease diagnosis and medication dosing are beyond the scope of a care profile. For a sick fish, confirm symptoms against a reputable veterinary or fish-health reference before treating.
How Long Do Colombian Tetras Live?
With good care, Colombian tetras live 3–5 years. Reaching the upper end of that range depends on consistent water quality, an appropriately sized school, a varied diet, and avoiding chronic stress from incompatible tank-mates or overcrowding. Most captive-bred fish sold in stores are juveniles, so you typically get the full lifespan from purchase — unlike some species sold as adults. A well-established school in a planted, properly maintained tank is a long-term centrepiece worth investing in.
Frequently asked questions
Are Colombian tetras aggressive?
They can be fin-nippers, especially in small groups or with slow, long-finned fish. Keep them in groups of six or more — ideally ten — and pair them with robust, similarly sized tank-mates; the fin-nipping behaviour drops dramatically when they have enough of their own species to school with.
How big do Colombian tetras get?
They reach about 6.5 cm (2.5 in), making them one of the larger common tetras — noticeably bigger than neon or cardinal tetras and better suited to a 30-gallon-plus tank with ample swimming space.
What you need to keep a colombian tetra
The baseline is a heated, filtered 114 L+ tank: a reliable heater to hold 24–28 °C (75–82 °F), a gentle filter that won't batter a colombian tetra in the current, and a tight-fitting lid. Cycle the tank fully before adding any fish.
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