Home / Fishes / Gouramis, bettas, snakeheads / Peaceful betta
No federal permit to keepPeaceful betta
Betta imbellis
Fishes › Gouramis, bettas, snakeheads (Anabantiformes) › Osphronemidae (Gouramis and bettas)
The peaceful betta or crescent betta (Betta imbellis) is a species of gourami native to Southeast Asia. Betta imbellis has a pair of suprabranchial chambers that each house a labyrinth organ, a complex bony structure lined with thin, highly…

Care at a glance
Species-specific values
Values researched for this exact species. Where they differ from the group guide below, follow these. Air, surface and water temperatures are listed separately, and each source is kept as published rather than averaged.
| Water temperature | 68–82 °F (20–28 °C) Maintenance recommendations from this source; do not replace with a multisource average. | 253 |
| Water pH | 5–7.5 Maintenance recommendations from this source; do not replace with a multisource average. | 253 |
| Water general hardness | 1–10 dGH Maintenance recommendations from this source; do not replace with a multisource average. | 253 |
| Adult standard length | 60 mm Maximum standard length reported by source; excludes caudal fin, not total body length. | 253 |
| Minimum tank base | length: 45 cm; width: 30 cm Minimum aquarium base recommended by this source, not a tank-volume specification. For a pair with cover. | 253 |
| Social | A pair can be maintained in a suitably covered species aquarium. Do not extrapolate domestic B. splendens solitary housing to every Betta species. | 253 |
| Water flow | Gentle filtration; avoid strong current. Leave access to humid air above the water and use a secure cover. | 253 |
Species-specific aquarium care
- Tank: At least 24 in long and 12 in front to back for one adult (adults commonly reach about 2.4 in / 6 cm).
- Water: Freshwater.
- Temperature: 75–82°F (range recorded for this species).
- pH: 6–7.
- Hardness: 5–19 dGH.
- Layout: Uses both the bottom and open water: give open swimming space plus cover near the substrate.
Calculated from this species' own FishBase record: tank size from its typical adult length and swimming zone, water values from its recorded ranges. The group guide below fills in general care.
Care guide
Species care notes
- Tank: a base of at least 18 × 12 in (roughly 11 US gallons); space needed is rated “modest tank”.
- Water: a fairly wide range, from slightly acidic to slightly alkaline, 68–82 °F, pH 5–7.5, 1–10 dGH.
- Behaviour: temperament species tank; in a pair; not a community fish.
- Difficulty: Moderate (Seriously Fish rating).
Short excerpts from the species profile:
- Setup: “This species fares best in a well-planted, shady aquarium with plenty of surface cover in the form of tall stem plants, floating types such as Salvinia or Riccia spp., or tropical lilies from the genus Nymphaea.”
- Diet: “Likely to prey on aquatic and terrestrial invertebrates in nature.”
- Tankmates: “Not recommended for the standard community aquarium.”
From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167
Bettas (fighting fish)
Applies to most species in this group. Habitat: Shallow rice paddies and marshes. Individual species can differ, so compare with the species numbers above and the linked sources.
Housing & setup
- A heated, filtered tank of at least 5 gallons, with gentle flow and plants.
- Domestic B. splendens should generally be maintained alone. Other Betta species need their own compatibility plan; B. imbellis can be maintained as a pair with adequate cover.
Diet
- Betta pellets plus frozen foods.
Social life
- Use species-specific social housing: B. splendens alone under the detailed Seriously Fish recommendation; B. imbellis may be housed as a compatible pair.
Health watch
- Fin rot in dirty water; never keep bettas in tiny unheated bowls.
Understanding the animal
About this animal
About this animal
The labyrinth organ is a morpho‐physiological adaptation that allows the B. imbellis to extract oxygen from air.
Quoted from the Wikipedia article “Peaceful betta” (CC BY-SA 4.0) 174
In the wild
In the wild
From this species’ own FishBase record (habitat, bottom type, water and breeding data), not its family. Good care copies these conditions.1
| Where it lives | Lives in freshwater. Uses both the bottom and open water. Occurs usually in stagnant pools and ditches in clear to brown water. |
| Water it lives in | Freshwater, 75–82 °F (24–28 °C), pH 6–7, hardness 5–19 dH. |
| Climate | Tropical climate. |
| Behavior to plan for | Breeding: nesters. |
What this means for care
- Keep water within its wild range, 75–82 °F.
Native climate (measured)
Native climate (measured)
| Warm-season highs | about 91°F (up to 94°F in the hottest sampled areas) |
| Cool-season lows | about 71°F (down to 67°F in the coldest sampled areas) |
| Average temperature | 78–82°F across sampled records |
| Relative humidity | 78–82% on average (driest month about 73%) |
| Rainfall | about 2052 mm a year |
Measured at 37 wild occurrence records sampled against WorldClim 2.1 climate data (1970–2000 averages). Air conditions in the range are ecological context, not enclosure settings: microhabitats such as burrows, leaf litter or basking rocks can be cooler, warmer or more humid.
From the sources
From the sources
Quoted from the matching sections of reputable sources for this exact species. Specialist databases are used first; Wikipedia (community-edited, CC BY-SA 4.0) only fills gaps. Other sources are short credited quotes.
| Overview | The peaceful betta or crescent betta (Betta imbellis) is a species of gourami native to Southeast Asia. Betta imbellis has a pair of suprabranchial chambers that each house a labyrinth organ, a complex bony structure lined with thin, highly vascularised respiratory epithelium. The labyrinth organ is a morpho‐physiological adaptation that allows the B. imbellis to extract oxygen from air. This adaptation allows the species to persist in extreme conditions. — Wikipedia (community-edited) |
| Where it lives | Home ranges Population dynamics Growth parameters Max. ages / sizes Length-weight rel. Length-frequencies Mass conversion Recruitment Abundance Life cycle Reproduction Maturity Maturity/Gills rel. — FishBase |
| Wild diet | In the wild, Betta imbellis feeds on terrestrial and aquatic invertebrates. In captivity, the species is fed live or frozen food like Daphnia, Artemia or bloodworms. — Wikipedia (community-edited) |
| Reproduction | Eggs shrink to the bottom and were then collected by one or both parents and were embedded among the foam bubbles in the nest. — FishBase |
| Appearance and size | Betta imbellis grows to a maximum standard length of 6 cm. It can live for up to 5 years. — Wikipedia (community-edited) |
| Biology | Facultative air-breathing; Occurs usually in stagnant pools and ditches in clear to brown water. Found also in lowland swamps and paddy field. Bubble nest builder species. — FishBase |
| Conservation | Betta imbellis is listed as least concern by the IUCN Red List. It is still threatened by pollution and hybridization with released domesticated bettas (Siamese fighting fish) and other bettas in the B. splendens complex. — Wikipedia (community-edited) |
Data and studies
The numbers
The numbers
Each bar is what one source reports. Where several sources weigh in, the dashed gold band marks their average.
Adult length
Maximum recorded length. Measured as standard length (snout to the base of the tail, not counting the tail fin). Fish in home aquariums often stay smaller than wild records.
Water temperature
Range the species tolerates in nature; aim for the middle.
Minimum tank footprint
Seriously Fish recommends a tank base of at least 18 × 12 in (about 11 US gallons).
Sources for this sheet
- FishBase (Froese & Pauly, eds.), version 24.07 Peer-reviewed researchThe global scientific database on fishes, maintained by a consortium of research institutions; every value is referenced.
- Seriously Fish species profiles Experienced keeper or breederLong-running aquarium reference written and peer-checked by experienced fishkeepers and ichthyologists; each profile covers habitat, tank size, water, diet, behaviour and breeding.
- Merck Veterinary Manual: Management of aquarium fish Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Merck Veterinary Manual: Types and features of aquatic systems Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Merck Veterinary Manual: Nutritional diseases of fish Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Seriously Fish — Betta splendens Zoo, university or veterinaryAdded in the 2026 source-checked care-guide review.
- Seriously Fish — Betta imbellis Zoo, university or veterinaryAdded in the 2026 source-checked care-guide review.
- Wikipedia (species article) Community referenceFree encyclopedia; useful overviews with their own citations. Intro text is quoted under CC BY-SA 4.0.
- iNaturalist (captive observations) Community referenceCommunity observation platform run by the California Academy of Sciences and National Geographic; observations marked captive show animals living in homes, zoos and aquariums.
