Should I buy it?
Columbian Tetra
Hyphessobrycon columbianus
Also known as: red and blue columbian tetra, blue-red columbian
A 5 cm steel-blue tetra tough enough to shrug off what kills cardinals — and a reliable fin-nipper. Eight or more, no trailing fins anywhere in the tank, and it earns its place.
Columbian Tetra tank mates · 80L tank size hub
peaceful · beginner care
Sources & confidencemedium · partially verified · beginner: good
Typical care sources — real tanks still vary. Numbers here are a careful starting point. Your tap water, tank size, and habits decide the rest. How we evaluate.
Best for: Planted tanks of 80L or more built around one confident mid-water school, with short-finned neighbours only.
Avoid if: You keep bettas, guppies or angelfish — columbians nip trailing fins reliably, not occasionally.
Common mistakeBuying Columbian tetras as a tough neon alternative for a betta community is the classic fin-shred story. The nipping starts quickly and does not stop because the betta “has a calm temperament.” Keep a school of six or more with other short-finned fish, or skip the pairing entirely. The mistake is solving neon deaths by importing a tetra that treats long fins as targets.
Top things that go wrong
- Fin-nipping risk in typical community layouts. Will nip long fins or slow fish when the school is too small, bored, or kept in a short tank.
- Group welfare — not a solo display fish. Plan at least **8** together for normal behaviour; smaller groups often mean stress, colour loss, or nipping depending on species.
- Shrimp & snails. Cherry shrimp and other dwarfs can coexist with peaceful small fish; baby shrimp are food for almost anything that finds them.
What most shops don't tell you
- 1.Shops sell Columbians as hardy community tetras for any peaceful tank. What that pitch skips is fin interest: bettas, angelfish, and fancy livebearers often pay for the “robust” label. They are a strong school for the right neighbours, not a universal filler. Buy them for active midwater with short fins, not as insurance next to a show betta.
- 2.Bought as a robust alternative to neons for a betta community. The columbians shred the betta's fins within weeks.
- 3.Trio stocking. Like silver tips, a trio redirects nipping at the slowest tank mate.
- 4.Less fragile than cardinals and brighter than rummies, but stronger nipping behaviour means no long-finned tank mates. A school of eight or more in a planted 80L holds the nipping internal to the species.
About this species
- Black phantom tetra80L min · same group, comparable tank size
- Penguin tetra80L min · same group, comparable tank size
- Rosy Tetra80L min · same group, comparable tank size
- Rummy Nose Tetra80L min · same group, comparable tank size
- Splash tetra80L min · same group, comparable tank size
- Beckford Pencilfish60L min · same group, similar adult size
- Black Neon Tetra60L min · same group, similar adult size
- Bloodfin tetra60L min · same group, similar adult size
- Amano Shrimpalso beginner peaceful, similar tank size
- Beckford Pencilfishalso beginner peaceful, similar tank size
- Black Neon Tetraalso beginner peaceful, similar tank size
- Black phantom tetraalso beginner peaceful, similar tank size
- Bloodfin tetraalso beginner peaceful, similar tank size
- Bristlenose Plecoalso beginner peaceful, similar tank size
No reverse lookups listed yet.
Plan grid
Key limits are above. Here: pH band, swim level, bioload, and activity.
Swim zones
Care snapshot
Quick compare before you buy. Not a score of how “good” the fish is.
- Beginner ease78
- Peacefulness68
- Community fit42
- Small-tank fit100
- Hardiness76
- Energy86
Numbers are deterministic planning indices from Fishori fields — not a scientific score of your individual fish.
Example setups
Starting points only. Run the pair checker for every fish you add.
Prioritise 8+ of Columbian Tetra in 80L+ with filtration sized for messy feeding — add only mates that already pass pair checks with this species.
Compatibility
Tank mates for Columbian Tetra
Usually safer (engine GOOD): Harlequin Rasbora. Conditional (CAUTION — read the pair page before buying): Angelfish, Bristlenose Pleco, Corydoras Catfish, Dwarf Gourami, Guppy. Avoid (RISKY): Betta. Every name links to a live pair check — the lists are a shortlist, not a stocking plan.
Usually safer
Open a pair page with this fish as the starting point.
Needs planning
Read the blocking rule on each pair page before experimenting.
Usually avoid
Do-not-stock combinations on conservative hobby rules.
Compare with
Run a real pair check: Columbian Tetra + Harlequin Rasbora
Behaviour and temperament
Columbian tetras stay calm inside a proper school and redirect energy at trailing fins once numbers drop or a slow long-finned fish shares the tank. The peaceful tag holds for midwater dither work with robust neighbours; it does not hold beside bettas or fancy guppies. Brief in-school chasing is normal sorting. Persistent nipping at one isolated target is the ownership problem people mislabel as “tetra aggression.”
What sets them off
- long-finned tank mates
- small groups
Fin nipping: Will nip long fins or slow fish when the school is too small, bored, or kept in a short tank.
Predation: Not a predator toward similarly sized community fish; fry and dwarf shrimp are still fair game for most species.
Territory: Not strongly territorial, but still needs room so its working space does not overlap the next fish.
Planted tanks: excellent — easy plant ideas
In the glass: typical and warning signs
- Active midwater school when six or more; colour holds with regular frozen foods.
- In-school chasing is common sorting, not a reason to break the group up.
- Washed colour and hanging at the back after poor feeding or tiny groups.
- Trio stocking that redirects nipping at the slowest tank mate.
- Fin-nipping of bettas and fancy livebearers is common and persistent.
- Shredded long fins within weeks → remove the tetras or the long-finned fish.
Fish behaviour can vary between individuals and tank setups. Always observe new fish closely after introduction.
Water, food, and grouping
Hardness
soft
Diet
omnivore
They take flake and micro-pellets in the midwater rush and still lose colour on a single dry food. Offer a quality staple plus frozen daphnia or bloodworm a few times a week, and make a second pass so the back of the school eats. Growing groups need small frequent meals more than one heavy dump. If only the boldest two are thick and the rest look washed, you under-fed the school.
Shrimp & snails
Cherry shrimp and other dwarfs can coexist with peaceful small fish; baby shrimp are food for almost anything that finds them.
Eight or more. Smaller groups redirect nipping to long-finned tank mates.
- Eight or more from the same source.
- Tank mates without trailing fins.
- Soft to slightly acidic water (pH 6.0 to 7.5).
- An 80L+ planted setup with a clear mid-water swim path.
- Tank volume meets or exceeds 80L published minimum for adults.
- You can stock at least 8 individuals (group welfare).
- Heater can hold 22–28°C without cooking cooler-water tank mates.
- No known fin-nippers paired with long-finned fish unless you accept documented risk.
Explore and stocking hubs
Tank-mates hub, matching guides, category peers, and litre stocking lists around this species’ minimum tank.
Plan with tools
Check mates as pairs first, then add this fish in the tank builder for the full stocking.
Filtration & heating
A 80L minimum tank needs a filter rated for at least 320L/hr turnover and a heater to hold 22–28°C reliably.
Plant suggestions
Columbian Tetra does well in planted tanks. Plants compatible with 22–28°C and pH 6–7.5:
Research: partially verified · Confidence: medium · 2 linked source(s). We do not invent citations.
How Fishori evaluates compatibility (same logic as pair and tank tools).
- Seriously Fish. Hyphessobrycon columbianus
Primary: species page covering Colombian range, water chemistry preferences, and the documented fin-nipping under-stocking issue.
- Practical Fishkeeping. Columbian Tetra Profile
Secondary: editor coverage of the species' robust size, schooling needs, and the betta-incompatibility warning.
Evidence notes
- Columbian tetras are sometimes mislabelled in shops as 'red-blue tetra' alongside several unrelated species. The Hyphessobrycon columbianus from Colombia is the specific fish covered here.
- Larger and tougher than most Hyphessobrycon tetras. A group of eight in a 100L acts confident in the open, where smaller tetras would hide in cover.
Featured compatibility checks
Curated pair pages for Columbian Tetra. Each opens a full verdict — not just a list label.
Common questions about Columbian Tetra
- How big do Columbian Tetra get?
- Columbian Tetra adults reach about 5 cm. Shop fish look smaller; stock for the adult length.
- What size tank does Columbian Tetra need?
- 80L is the planning floor for adult swimming space and bioload. A 100L+ tank is the more comfortable long-term footprint. Length and depth matter as much as raw litres for active or territorial fish.
- Are Columbian Tetra aggressive?
- Columbian tetras stay calm inside a proper school and redirect energy at trailing fins once numbers drop or a slow long-finned fish shares the tank. The peaceful tag holds for midwater dither work with robust neighbours; it does not hold beside bettas or fancy guppies. Brief in-school chasing is normal sorting. Persistent nipping at one isolated target is the ownership problem people mislabel as “tetra aggression.”
- Do Columbian Tetra need to be kept in a group?
- Eight or more. Smaller groups redirect nipping to long-finned tank mates.
- What is the most common mistake with Columbian Tetra?
- Buying Columbian tetras as a tough neon alternative for a betta community is the classic fin-shred story. The nipping starts quickly and does not stop because the betta “has a calm temperament.” Keep a school of six or more with other short-finned fish, or skip the pairing entirely. The mistake is solving neon deaths by importing a tetra that treats long fins as targets.
- What fish can live with Columbian Tetra?
- The Columbian Tetra profile lists Harlequin Rasbora among its safer pairings (engine-checked GOOD). Angelfish, Bristlenose Pleco, Corydoras Catfish, Dwarf Gourami are conditional (CAUTION): workable only with the specific conditions on each pair page. Avoid Betta (RISKY). Run the pair checker for your exact water and tank size before stocking.