Should I buy it?
Betta
Betta splendens
Also known as: siamese fighting fish, betta splendens (trade name)
Best kept solo. A community betta tank is a coin-flip even with the right tank mates. A 75L+ planted sorority setup is barely better odds.
Betta tank mates · 30L tank size hub
semi-aggressive · beginner care
Sources & confidencehigh · 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.
For a single-species setup, this fish is often a good choice. In community tanks, compatibility depends heavily on tank mates.
Best for: Single-fish 20L+ planted tanks, or experienced keepers building a betta-led setup after a live pair check for every mate.
Avoid if: You wanted a community fish; you keep guppies (males look like rivals); or you can only commit to a 5L bowl.
Common mistakeColourful guppies in a small tank with a male betta are a regular disaster. The betta often reads every bright flash as a rival to drive off, so the guppies spend their lives fleeing or losing fins. If you want community colour, choose quieter tank mates or keep the betta alone. A pretty mixed display in the shop does not mean those fish will share a short tank at home.
Top things that go wrong
- Shrimp & snails. Shrimp are a gamble with this fish; some ignore them, some clear a colony in days.
What most shops don't tell you
- 1.Sorority setups get marketed in fish shops far more than they actually work for most keepers. A group of females in a planted tank can look peaceful for months and then cascade into damage. Treat that approach as advanced and optional, not as the default way to keep bettas socially. One well-kept male is still the ownership path that fails least often.
- 2.Long-finned males in strong filter flow with no rest spots. They tire on the current and shred fins on equipment. Damage gets blamed on tank mates before flow gets cut.
- 3.Feeding only dry pellets. Bettas go on hunger strikes when bored of one food, and pellets swell in the stomach when eaten too fast.
- 4.Two males in one tank end in a dead fish, sometimes the same day. Pick tank mates that are fast, calm, and dull-coloured so they do not provoke a fight. Buy a lid before the fish. They jump.
- 5.Male bettas are territorial; tank mate choice is individual-dependent.
About this species
Bettas are labyrinth fish that gulp air at the surface as well as breathe through gills. A male will fight any other male on sight, and reads most long-finned or bright fish as another male.
- Honey Gourami40L min · same group, similar adult size
- Sparkling Gourami40L min · same group, similar adult size
- Dwarf Gourami60L min · same group, similar adult size
- Chocolate gourami80L min · same group, similar adult size
- Croaking gourami80L min · same group, similar adult size
- Pearl Gourami100L min · same fish family
- Paradise fish120L min · same group, similar adult size
- Opaline gourami150L min · same fish family
- Ghost Shrimpalso beginner semi-aggressive, similar tank size
- Pygmy Corydoras tank matesnames this fish as a conditional pairing — read the pair page conditions
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 ease63
- Peacefulness44
- Community fit22
- Small-tank fit100
- Hardiness79
- Energy54
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.
Avoid “one of everything” baskets — Betta belongs in a plan built around territory, line-of-sight breaks, and matched water chemistry.
Compatibility
Tank mates for Betta
No unconditional “safe” tank mates are listed for Betta — this shortlist has CAUTION pairings that need specific conditions and RISKY pairings to avoid. Conditional (CAUTION — read the pair page before buying): Guppy. Avoid (RISKY): Tiger Barb. 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.
None listed. Use the pair checker before mixing.
Needs planning
Read the blocking rule on each pair page before experimenting.
Usually avoid
Do-not-stock combinations on conservative hobby rules.
No safe-mate list on this record yet. Use the fish index to find species with similar care, then run a pair check before you buy.
Behaviour and temperament
Bettas are solitary and territorial by habit, not by poor manners you can train away. Two males in sight of each other often end with one badly hurt or dead the same day. Sororities in a large planted tank are marketed as the social alternative, yet many still collapse within a year even when the stocking chart looked tidy. If you want a calm ownership story, plan for one male in his own space unless you are deliberately taking on an advanced project.
What sets them off
- Another male betta, or anything mirror-shiny
- Colourful or long-finned tank mates that read as rival males
- Cramped tanks with nowhere to break line of sight
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: Holds a patch (cave, corner, or surface). Break sight lines so neighbours can pass.
Planted tanks: good — easy plant ideas
In the glass: typical and warning signs
- A male often holds a surface territory and may flare at reflections and rivals.
- Long stretches still under a leaf can be rest rather than illness when appetite is good.
- Clamped fins and no flare after a move usually mean give cover and still water for a week first.
- Gasping with a strong filter current aimed at the surface is a flow problem to fix.
- Two males in sight of each other will often fight to injury, with no reliable exception.
- Sororities can look calm for months and then cascade; treat them as advanced, not default.
- Any torn fin on a tank mate means remove the betta or the target the same day.
- Mirror-flaring for hours is stress; break the reflection rather than trying to train it.
Fish behaviour can vary between individuals and tank setups. Always observe new fish closely after introduction.
Water, food, and grouping
Hardness
soft
Diet
carnivore
Pellets alone are a quiet failure mode that shows up after the novelty wears off. Many bettas refuse a single dry food after weeks, and dry pellets can swell after a fish gulps them too fast. Rotate a frozen or freeze-dried protein a few times a week, and offer tiny portions the fish can finish in about two minutes. Bored hunger strikes and bloating are easier to prevent than to explain after the fact.
Shrimp & snails
Shrimp are a gamble with this fish; some ignore them, some clear a colony in days.
Betta is fine singly or as a researched pair — check behaviour before doubling up.
- Hold 24 to 30 °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.
- Footprint: short wide tanks and tall narrow tanks fish differently for the same volume. Match the tank shape to the swim pattern, not just the litre count.
- Tank volume meets or exceeds 20L published minimum for adults.
- Heater can hold 24–30°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 20L minimum tank needs a filter rated for at least 80L/hr turnover and a heater to hold 24–30°C reliably.
Plant suggestions
Betta does well in planted tanks. Plants compatible with 24–30°C and pH 6.5–7.5:
Research: 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. Betta splendens
Primary: aquarium size, water chemistry, behaviour, and compatibility (URL verified in upgrade script; recheck if site content changes).
- FishBase. Betta splendens
Secondary: taxonomy, distribution, and maximum length in nature; cross-check with aquarium import lines and measured tank parameters.
- Wikipedia. Betta splendens
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
- 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 Betta. Each opens a full verdict — not just a list label.
Common questions about Betta
- How big do Betta get?
- Around 6 to 7 cm including the tail fin. The body alone is smaller. The defended territory is larger than either, which is why a betta in a strip tank patrols every centimetre.
- What size tank does Betta need?
- 20 litres is the practical minimum for a tank that holds heat, runs a real filter, and has planting. 25 litres or more is the more comfortable long-term home. The 5L cubes you see in shops crash temperature overnight and overload on one feeding.
- Are Betta aggressive?
- Bettas are solitary and territorial by habit, not by poor manners you can train away. Two males in sight of each other often end with one badly hurt or dead the same day. Sororities in a large planted tank are marketed as the social alternative, yet many still collapse within a year even when the stocking chart looked tidy. If you want a calm ownership story, plan for one male in his own space unless you are deliberately taking on an advanced project.
- What is the most common mistake with Betta?
- Colourful guppies in a small tank with a male betta are a regular disaster. The betta often reads every bright flash as a rival to drive off, so the guppies spend their lives fleeing or losing fins. If you want community colour, choose quieter tank mates or keep the betta alone. A pretty mixed display in the shop does not mean those fish will share a short tank at home.
- What fish can live with Betta?
- This profile currently has no curated unconditional safe-mates shortlist for Betta. Other species may still return GOOD in the pair checker, so check the exact pair rather than treating this shortlist as exhaustive. Guppy is conditional (CAUTION): workable only with the specific conditions on its pair page. Avoid Tiger Barb (RISKY). Run the pair checker for your exact water and tank size before stocking.