Should I buy it?
Chili Rasbora
Boraras brigittae
Also known as: chili, boraras brigittae
A 2 cm nano fish that shows full red colouring only in soft blackwater with tannins. Hard, bright, busy tanks wash the colour out completely.
Chili Rasbora tank mates · 30L tank size hub
peaceful · intermediate care
Sources & confidencehigh · partially verified · beginner: caution
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: Blackwater nano planted tanks 20–40L at pH 5–6.5 with dark substrate, tannins, and no active predators.
Avoid if: Your tap water is hard, you run bright lighting without tannins, or you keep any fish over 5 cm.
Common mistakeKeeping chili rasboras in soft tap water without tannins is how keepers invent pale pink fish that never look like the bag. Blackwater chemistry and leaf litter matter. Eight or more in a mature soft nano beats a hard bright handful every time — colour is husbandry, not luck.
Top things that go wrong
- 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.Myth: chili rasboras stay bright red in any soft nano community without tannins or a real school. Reality: they need blackwater-leaning chemistry and eight or more fish — hard bright kits and token numbers leave them pale and nervous for months.
- 2.Buying three or four to start. Chili Rasbora settles in a group of 8 or more. An understocked school sulks at the back of the tank and loses colour within a fortnight.
- 3.Tiny fish. Any large tank mates will eat them. Soft acidic water is essential. Best as a species tank or with other micro fish only.
About this species
Chili rasboras are 2 cm Indonesian micro fish from peat swamps. The deep red intensifies in soft acidic water over dark substrate. Easily missed in a planted nano without a school of eight or more.
- Celestial Pearl Danio30L min · same group, comparable tank size
- White Cloud Mountain Minnow40L min · same group, similar adult size
- Cherry Barb60L min · same group, similar adult size
- Dwarf pencilfish60L min · same group, similar adult size
- Harlequin Rasbora60L min · same group, similar adult size
- Lambchop / Espei rasbora60L min · same group, similar adult size
- Zebra Danio60L min · same group, similar adult size
- Golden / Beckford's pencilfish80L min · same group, similar adult size
- Cardinal Tetraalso intermediate peaceful, similar tank size
- Celestial Pearl Danioalso intermediate peaceful, similar tank size
- Clown Killifishalso intermediate peaceful, similar tank size
- Dwarf pencilfishalso intermediate peaceful, similar tank size
- Golden dwarf cichlid (Nannacara)also intermediate peaceful, similar tank size
- Green neon tetraalso intermediate peaceful, similar tank size
- Adolfoi cory tank matesnames this fish as a conditional pairing — read the pair page conditions
- Black phantom tetra tank mateslists this fish among its safer mates
- Celestial Pearl Danio tank matesnames this fish as a conditional pairing — read the pair page conditions
- Checkerboard cichlid tank mateslists this fish as a safe and recommended mate
- Chocolate gourami tank mateslists this fish as a safe and recommended mate
- Clown Killifish tank mateslists this fish as a safe and recommended mate
- Croaking gourami tank mateslists this fish as a safe and recommended mate
- Dwarf pencilfish 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 ease38
- Peacefulness90
- Community fit72
- Small-tank fit100
- Hardiness54
- Energy24
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 Chili Rasbora in 20L+ with filtration sized for messy feeding — add only mates that already pass pair checks with this species.
Compatibility
Tank mates for Chili Rasbora
Usually safer (engine GOOD): Otocinclus. Conditional (CAUTION — read the pair page before buying): Betta, Celestial Pearl Danio, Pygmy Corydoras, Tiger Barb. Avoid (RISKY): Angelfish, 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: Chili Rasbora + Otocinclus
- Try Otocinclus — open the pair check.
Behaviour and temperament
Chili rasboras are peaceful micro schoolers that stay calmer in groups of eight or more in soft tannin water. They do not bully neighbours. Stress shows as fading, hiding, and scattered swimming when chemistry is hard bright or the school is only a handful.
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
- Eight or more hold midwater as a red micro-school among plants and leaf litter.
- Tight grouping after a fright is normal — give cover to reform.
- Pale colour without tannins usually means chemistry and light first.
- A scattered handful needs more of their own kind before a different staple.
- Low listed risk as aggressors.
- Large or boisterous fish are the usual failure modes — not chili malice.
- Add leaf litter and grow the school before chasing colour-enhancer myths.
- Remove hyper feeders that steal every micro-food portion.
Fish behaviour can vary between individuals and tank setups. Always observe new fish closely after introduction.
Water, food, and grouping
Hardness
soft
Diet
omnivore
Chili rasboras are tiny omnivores that take micro-foods, crushed flake, and fine frozen items in a school of eight or more. Food that sinks past them too fast leaves the school thin in a busy nano. Offer tiny portions in soft tannin-stained water, keep surface calm, and never treat them as hardy livebearer leftovers eaters.
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 8+ together. Smaller groups stress and lose colour.
- Hold 24 to 28 °C steadily on a real thermometer, not the dial on the heater.
- Aim for pH 4 to 7 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 8 or more from the same tank on the same day before adding any centrepiece fish.
- Tank volume meets or exceeds 20L published minimum for adults.
- You can stock at least 8 individuals (group welfare).
- Heater can hold 24–28°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 20L minimum tank needs a filter rated for at least 80L/hr turnover and a heater to hold 24–28°C reliably.
Plant suggestions
Chili Rasbora does well in planted tanks. Plants compatible with 24–28°C and pH 4–7:
Research: partially verified · Confidence: high · 3 linked source(s). We do not invent citations.
How Fishori evaluates compatibility (same logic as pair and tank tools).
- Seriously Fish. Boraras brigittae
Primary: aquarium size, water chemistry, behaviour, and compatibility (URL verified in upgrade script; recheck if site content changes).
- FishBase. Boraras brigittae
Secondary: taxonomy, distribution, and maximum length in nature; cross-check with aquarium import lines and measured tank parameters.
- Wikipedia. Boraras brigittae
Secondary: general species context; verify all husbandry numbers against a dedicated aquarium care sheet and your test kit, not a single table row.
Evidence notes
- The Seriously Fish profile for the binomial in this record was successfully reached as the primary aquarium reference.
- FishBase contributes natural-range size and habitat context. Translate those numbers through your heater, your water report, and your tank footprint before stocking.
- Wikipedia is only cited if the article URL returned OK. Use it for orientation, not as the only care sheet for an import.
- All compatibility text reflects typical hobby experience and the Fishori model. Individual fish, shop stress, and the order tank mates are added in can still defy a single-paragraph label.
Featured compatibility checks
Curated pair pages for Chili Rasbora. Each opens a full verdict — not just a list label.
Common questions about Chili Rasbora
- How big do Chili Rasbora get?
- Chili Rasbora adults reach about 2 cm. Shop fish look smaller; stock for the adult length.
- What size tank does Chili Rasbora need?
- 20L is the planning floor for adult swimming space and bioload. A 24L+ tank is the more comfortable long-term footprint. Length and depth matter as much as raw litres for active or territorial fish.
- Are Chili Rasbora aggressive?
- Chili rasboras are peaceful micro schoolers that stay calmer in groups of eight or more in soft tannin water. They do not bully neighbours. Stress shows as fading, hiding, and scattered swimming when chemistry is hard bright or the school is only a handful.
- Do Chili Rasbora need to be kept in a group?
- Schooling species — buy 8+ together. Smaller groups stress and lose colour.
- What is the most common mistake with Chili Rasbora?
- Keeping chili rasboras in soft tap water without tannins is how keepers invent pale pink fish that never look like the bag. Blackwater chemistry and leaf litter matter. Eight or more in a mature soft nano beats a hard bright handful every time — colour is husbandry, not luck.
- What fish can live with Chili Rasbora?
- The Chili Rasbora profile lists Otocinclus among its safer pairings (engine-checked GOOD). Betta, Celestial Pearl Danio, Pygmy Corydoras, Tiger Barb are conditional (CAUTION): workable only with the specific conditions on each pair page. Avoid Angelfish, Oscar (RISKY). Run the pair checker for your exact water and tank size before stocking.