Home / Fishes / Gouramis, bettas, snakeheads / Elephant ear gourami
No federal permit to keepElephant ear gourami
Osphronemus exodon
Fishes › Gouramis, bettas, snakeheads (Anabantiformes) › Osphronemidae (Gouramis and bettas)
The elephant ear gourami (Osphronemus exodon) is a large species of gourami native to the Mekong river basin in Thailand, Laos, and Cambodia and Vietnam.
Intro from Wikipedia (CC BY-SA 4.0)
Care at a glance
Species-specific aquarium care
- Tank: At least 144 in long and 48 in front to back for one adult (adults commonly reach about 23.6 in / 60 cm).
- Water: Freshwater.
- Layout: An open-water swimmer: needs long, open swimming space with few obstacles.
- Diet: FishBase classes it as a omnivore.
- Availability: Rarely or never seen in the aquarium trade; expect to source it from specialists or not at all.
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 71 × 24 in (roughly 171 US gallons); space needed is rated “very large tank”.
- Water: a fairly wide range, from slightly acidic to slightly alkaline, 68–86 °F, pH 6.5–8, 5–25 dGH.
- Difficulty: Moderate (Seriously Fish rating).
Short excerpts from the species profile:
- Setup: “Provide shelter in the form of water-worn rocks and large pieces of bogwood.”
- Diet: “Primarily herbivorous, food can consist of a decent dried vegetable pellet with the addition of vegetation such as spinach or lettuce, and fruits and vegetables including cucumber, tomato etc.”
- Tankmates: “Some adults may become very aggressive but this is often due to being kept in an aquarium that is too small.”
- Breeding: “Not yet reported in aquaria, but probably breeds in a similar fashion to its cousin O.”
From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167
Gouramis and labyrinth fish
Applies to most species in this group. Habitat: Warm, still, vegetated waters. Individual species can differ, so compare with the species numbers above and the linked sources.
Housing & setup
- Planted, calm tanks with floating plants; they breathe air at the surface, so leave a gap under the lid.
Diet
- Food acceptance is species-specific. Parosphromenus deissneri needs tiny live invertebrate foods and commonly refuses dried foods; a pellet/flake staple cannot cover every labyrinth fish.
Health watch
- Males are territorial; dwarf gourami iridovirus.
Understanding the animal
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, in rivers and streams. Occurs in pools of large rivers and in flooded forests during the rainy season. Feeds mainly on plant matter including fruits, leaves, and flowers, with some insects and crustaceans. Known to reproduce in non-flowing waters near the river shore during lowest water levels. |
| Water it lives in | Freshwater. |
| Climate | Tropical climate. |
| Behavior to plan for | Breeding: nesters. |
Native climate (measured)
Native climate (measured)
| Warm-season highs | about 93°F (up to 95°F in the hottest sampled areas) |
| Cool-season lows | about 68°F (down to 66°F in the coldest sampled areas) |
| Average temperature | 79–82°F across sampled records |
| Relative humidity | 73–74% on average (driest month about 65%) |
| Rainfall | about 1857 mm a year, with strong wet and dry seasons |
Measured at 8 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 elephant ear gourami (Osphronemus exodon) is a large species of gourami native to the Mekong river basin in Thailand, Laos, and Cambodia and Vietnam. — 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 |
| Reproduction | Builds a small nest, made of leaves and roots of a plant named "gohk kai" in Takam, just below the Lee Pee Waterfalls in southern Laos. Eggs and young are guarded by one parent as observed in the Mekong basin at Stung Treng. — FishBase |
| Appearance and size | Adults can grow up to 60 cm. Like other species of the genus Osphronemus, juveniles and adults of this species have physical differences. Juveniles have 6 or 7 vertical stripes and a spot on the back, which fades as they get older. — Wikipedia (community-edited) |
| Biology | Obligate air-breathing; Occurs in pools of large rivers and in flooded forests during the rainy season. Feeds mainly on plant matter including fruits, leaves, and flowers, with some insects and crustaceans. Known to reproduce in non-flowing waters near the river shore during lowest water levels. — FishBase |
| Conservation | Elephant ear gouramis are listed as vulnerable by the IUCN. Dams in the Mekong disrupted the wet and dry season cycle which lowered the population of this species. — 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; aim for the middle.
pH
Water hardness
Minimum tank footprint
Seriously Fish recommends a tank base of at least 71 × 24 in (about 171 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 — Parosphromenus deissneri 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.
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