Should I buy it?
Zebra Danio
Danio rerio
Also known as: zebrafish (aquarium form)
Classic 'starter' fish that's actually misused. They're hyperactive jumpers that need long tanks and stress slow-moving fish.
Zebra Danio tank mates · 60L tank size hub
peaceful · beginner care
Sources & confidencehigh · verified · beginner: excellent
Checked against several solid care sources that mostly agree. Numbers here are a careful starting point. Your tap water, tank size, and habits decide the rest. How we evaluate.
Best for: Active community tanks 80L or more with lateral length for the constant motion.
Avoid if: Your tank is short, you keep slow long-finned fish (bettas, angels), or you want a calm aquarium.
Common mistakeAdding a handful of danios to a short nano tank as a calm starter school is the mistake that shows up for years. They need forward run, and in cramped water they stress every slow or long-finned neighbour with constant traffic. Keep them in a longer footprint — roughly 80 litres or more with open midwater — or choose a quieter species. Activity is not optional behaviour you can train away.
Top things that go wrong
- Group welfare — not a solo display fish. Plan at least **6** 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 often sell zebra danios as the harmless default school for any small community. What that pitch skips is pace: they are a racetrack species, not a backdrop. Bettas, angelfish, and other slow long-finned fish read that traffic as harassment even when no scales are lost. Buy them for motion in a long tank, not as filler for a calm display.
- 2.Three danios in a 30L. The species is a high-activity shoal that needs a real group in a long footprint.
- 3.Housing in hot discus or low-O₂ tanks without a temperature plan. Danios prefer cooler water than most tropicals.
- 4.Hardy in tap water. Tolerate 18 to 26 °C, a wider range than most tropicals. Keep six or more from the same tank.
About this species
Zebra danios are small Indian cyprinids that cruise the top half of the tank in a fast, constant school. Blue and silver horizontal stripes mark the flanks. They jump from any open gap.
- Cherry Barb60L min · same group, comparable tank size
- Dwarf pencilfish60L min · same group, comparable tank size
- Harlequin Rasbora60L min · same group, comparable tank size
- Lambchop / Espei rasbora60L min · same group, comparable tank size
- Golden / Beckford's pencilfish80L min · same group, similar adult size
- Pearl Danio80L min · same group, similar adult size
- White Cloud Mountain Minnow40L min · same group, similar adult size
- Celestial Pearl Danio30L min · same group, similar adult size
- Amano Shrimpalso beginner peaceful, similar tank size
- Assassin Snailalso 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
- Cherry Barb tank mateslists this fish as a safe and recommended mate
- Ghost Shrimp tank matesnames this fish as a conditional pairing — read the pair page conditions
- Hillstream Loach tank mateslists this fish as a safe and recommended mate
- Paradise fish tank matesnames this fish as a conditional pairing — read the pair page conditions
- Pearl Danio tank mateslists this fish as a safe and recommended mate
- White Cloud Mountain Minnow tank mateslists this fish as a safe and recommended mate
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 ease85
- Peacefulness90
- Community fit86
- Small-tank fit100
- Hardiness79
- 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.
Rough 90L+ layout: one calm centrepiece, 8–12 small tetras/rasboras, 6–8 corydoras-type bottom fish — verify every name in the pair checker before buying.
Safer directions include: Cherry Barb, Corydoras Catfish, Harlequin Rasbora.
Prioritise 6+ of Zebra Danio in 60L+ with filtration sized for messy feeding — add only mates that already pass pair checks with this species.
Compatibility
Tank mates for Zebra Danio
Usually safer (engine GOOD): Cherry Barb, Corydoras Catfish, Harlequin Rasbora, Neon Tetra, Platy. Conditional (CAUTION — read the pair page before buying): Betta, Tiger Barb. Avoid (RISKY): Oscar. 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: Zebra Danio + Cherry Barb
Behaviour and temperament
Zebra Danios keep moving once the school is large enough, and that motion is the point of keeping them. A group of six or more usually patrols the length of the tank together; three or four often park under the filter and look dull. Brief chasing inside the school is normal sorting, not a fight you need to break up. Stillness in a danio is the odd signal — test the water before you blame tank mates.
What sets them off
- Sudden crowding
- Poor water quality
Fin nipping: Not a habitual fin-nipper; stressed or crowded individuals can still test fins.
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
- Top-to-bottom dashes all day — the tank's metronome once the school is large enough.
- Six or more move as a pack; fewer hang under the filter and look dull.
- Stillness in a danio is wrong; test water before blaming tank mates.
- Clamped fins after a cold snap — they feel a drop that other fish shrug off.
- In-school chasing is sorting, not damage — unless one fish is pinned and stripped of scales.
- Pinning that lasts after you add numbers → rehome the target or thin the tank.
- Never the fish to remove first when a community goes wrong; they are usually the victims.
Fish behaviour can vary between individuals and tank setups. Always observe new fish closely after introduction.
Water, food, and grouping
Hardness
soft
Diet
omnivore
Danios snatch flake at the surface faster than most community fish, so midwater and bottom keepers can look full while the school is still hunting. Offer a second small pinch after the first rush settles, or use a mix of floating flake and a few micro-pellets that break apart. Frozen daphnia or bloodworm once or twice a week keeps condition on active fish that burn energy all day. If only the boldest two eat, 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.
Schooling species — buy 6+ together. Smaller groups stress and lose colour.
- Hold 18 to 26 °C steadily on a real thermometer, not the dial on the heater.
- Aim for pH 6.5 to 7.5 and a hardness you can re-test in two weeks. A one-time strip in the shop car park is not a water test.
- Schooling species. Buy 6 or more from the same tank on the same day before adding any centrepiece fish.
- Tank volume meets or exceeds 60L published minimum for adults.
- You can stock at least 6 individuals (group welfare).
- Heater can hold 18–26°C without cooking cooler-water tank mates.
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 60L minimum tank needs a filter rated for at least 240L/hr turnover and a heater to hold 18–26°C reliably.
Plant suggestions
Zebra Danio does well in planted tanks. Plants compatible with 18–26°C and pH 6.5–7.5:
Research: verified · Confidence: high · 4 linked source(s). We do not invent citations.
How Fishori evaluates compatibility (same logic as pair and tank tools).
- Seriously Fish. Danio rerio
Primary: aquarium size, water chemistry, behaviour, and compatibility (URL verified in upgrade script; recheck if site content changes).
- FishBase. Danio rerio
Secondary: taxonomy, distribution, and maximum length in nature; cross-check with aquarium import lines and measured tank parameters.
- Wikipedia. Danio rerio
Secondary: general species context; verify all husbandry numbers against a dedicated aquarium care sheet and your test kit, not a single table row.
- Wikipedia. Danio rerio (zebra danio)
Encyclopaedia overview; use specialist aquarium sources for your stock's real temperature/pH/footprint needs.
Evidence notes
- Care numbers are cross-checked across the linked sources and biased toward the conservative end; compatibility reflects typical hobby experience, not a lab prediction. Method and full source policy: /methodology.
Featured compatibility checks
Curated pair pages for Zebra Danio. Each opens a full verdict — not just a list label.
Common questions about Zebra Danio
- How big do Zebra Danio get?
- 5 to 6 cm. Always moving. The school looks bigger and busier than its actual size.
- What size tank does Zebra Danio need?
- 80L or more with at least 60 cm of length. Cube and column tanks frustrate them; they need horizontal cruising space.
- Are Zebra Danio aggressive?
- Zebra Danios keep moving once the school is large enough, and that motion is the point of keeping them. A group of six or more usually patrols the length of the tank together; three or four often park under the filter and look dull. Brief chasing inside the school is normal sorting, not a fight you need to break up. Stillness in a danio is the odd signal — test the water before you blame tank mates.
- Do Zebra Danio need to be kept in a group?
- Schooling species — buy 6+ together. Smaller groups stress and lose colour.
- What is the most common mistake with Zebra Danio?
- Adding a handful of danios to a short nano tank as a calm starter school is the mistake that shows up for years. They need forward run, and in cramped water they stress every slow or long-finned neighbour with constant traffic. Keep them in a longer footprint — roughly 80 litres or more with open midwater — or choose a quieter species. Activity is not optional behaviour you can train away.
- What fish can live with Zebra Danio?
- The Zebra Danio profile lists Cherry Barb, Corydoras Catfish, Harlequin Rasbora, Neon Tetra among its safer pairings (engine-checked GOOD). Betta, Tiger Barb are conditional (CAUTION): workable only with the specific conditions on each pair page. Avoid Oscar (RISKY). Run the pair checker for your exact water and tank size before stocking.