26 Anabantoids Fish Species - Gourami, Betta, Paradise Fish, and More
Photo by Tanmayee D on Openverse (CC BY 2.0)
Anabantoid fish-often called labyrinth fish-are a diverse, captivating group of species found primarily in Asia and Africa. They're named for their labyrinth organ, a specialized breathing structure that allows them to gulp air from the surface, thriving in low-oxygen environments. This guide covers 26 anabantoid fish species aquarium care requirements, from the aggressive Siamese fighting fish to peaceful gouramis, to help you select and maintain these remarkable fish.
Understanding Anabantoids: Key Characteristics
Anabantoids belong to the family Osphronemidae and are defined by their labyrinth organ-a folded tissue structure in the head that extracts oxygen from air. This adaptation lets them survive in stagnant, oxygen-poor waters common in their native swamps, rice paddies, and ditches.
All anabantoids share several traits:
- Air-breathing ability: They must have access to the surface to gulp air regularly.
- Bubblenesting behavior: Most species (though not all) build bubble nests for breeding, with males typically guarding eggs and fry.
- Territorial or peaceful tendencies: Ranging from highly aggressive (like Siamese fighting fish) to genuinely peaceful species.
- Preference for warm, soft water: Most thrive between 72-86°F (22-30°C), though some tolerate cooler temps.
- Tank cover requirement: Nearly all anabantoids can jump or climb out, so enclosures must be covered.
The Bettas: From Aggressive Fighters to Peaceful Pairs
Siamese Fighting Fish (Betta splendens)
The Siamese fighting fish is the most recognizable anabantoid. Wild populations in Thailand are short-finned and inconspicuous, but selective breeding has produced the vibrant, long-finned males found in the hobby today. Females retain rounded fins closer to the wild type.
Care essentials:
- Size: Up to 2.5 in (6 cm)
- Temperature: 75-86°F (24-30°C)-critical for health
- Behavior: Males are famously aggressive; the Thai name pla-kat means "biting and tearing fish"
- Housing: Males must be kept alone; they will fight to the death in confined spaces
- Tank mates: Avoid fin-nippers like tiger barbs and species with similar red coloration (e.g., red-tailed black sharks)
- Diet: Flake and small live foods
Breeding: Lower water to 6 in (15 cm), house males with multiple females. Males build bubble nests under floating plants. Fry are free-swimming about four days after spawning and can be sexed at 2-3 months old.
Slender Betta (Betta bellica)
One of the largest betta species, slender bettas are generally peaceful despite their scientific name (bellica = warlike).
Care essentials:
- Size: 4-5 in (10-12.5 cm)
- Habitat preference: Soft, acidic, peat-filtered water; 82°F (28°C)
- Diet: Prepared foods and small invertebrates; avoid large earthworms (choking risk)
- Behavior: Peaceful, though males can become aggressive during breeding
- Special needs: Must be covered (excellent jumpers); well-planted tank with bogwood
Breeding: Bubble nesters; challenging to spawn successfully. Fry hatch in ~1 day, become free-swimming in 3 days. Start on proprietary fry food.
Penang Mouth-Brooding Betta (Betta pugnax)
Unlike most bettas, this species is a mouthbrooder, not a bubblenester-a unique reproductive strategy among the group.
Care essentials:
- Size: Up to 4.75 in (12 cm)
- Habitat: Mountain streams with clear, fast-flowing water; 72-79°F (22-26°C)
- Water chemistry: Soft, slightly acidic; efficient filtration essential
- Diet: Primarily insectivorous; live foods preferred
- Tank setup: Shallow (4 in/10 cm for spawning), well-planted, with moderate water flow if possible
Breeding: Males retain eggs in their mouth for ~10 days until fry hatch and emerge. Young can be raised on brine shrimp nauplii from day one.
Wine Red Fighter (Claret Betta, Betta coccina)
A small, beautifully colored betta requiring specialized, acidic water conditions.
Care essentials:
- Size: Up to 2.25 in (5.5 cm)
- Habitat: Blackwater (tannin-rich) and clear streams; 77-81°F (25-27°C)
- Water chemistry: Soft, acidic (pH ~4.5); blackwater extract recommended
- Behavior: Agile and prone to jumping; prone to velvet disease
- Diet: Live foods (fresh, freeze-dried, frozen)
Breeding: Bubble nesters producing 30-60 eggs. Fry are delicate; start with infusoria, then brine shrimp. Adults may cohabitate with offspring until 2 months old.
Black Betta (Betta persephone)
The smallest betta species, adapted to tiny forest pools.
Care essentials:
- Size: ~1.5 in (4 cm)
- Habitat: Shallow forest water; soft, acidic (pH ~5.0); peat-filtered
- Behavior: Reclusive and shy
- Diet: Small prepared and live foods
Breeding: Bubble nesters; females lay ~40 eggs. Fry mature slowly, not breeding until 9 months old. Can cohabitate with adults in spacious tanks until males become territorial.
Peaceful Betta (Crescent Betta, Betta imbelis)
Despite the name, males of the aggressive Siamese fighting fish, this species is genuinely peaceful and allows multiple pairs in the same tank.
Care essentials:
- Size: Up to 2 in (5 cm)
- Behavior: Peaceful; courtship is gentle
- Aquarium: Can house multiple pairs together (unusual for bettas)
- Diet: Prepared and live foods
Breeding: Bubble nesters; spawning takes ~2 hours, producing ~15 eggs per spawning. Fry rearing parallels other bubble-nesting bettas.
Gouramis: Diverse and Colorful
Gouramis are the most diverse anabantoid group, ranging from tiny dwarf species to giant 28-inch fish. Most are peaceful bubble-nesters, though some require specialized water chemistry.
Pearl Gourami (Mosaic Gourami, Trichogaster leerii)
One of the most beautiful gouramis, pearl gouramis display pale blue spots across their bodies and are popular in planted aquariums.
Care essentials:
- Size: Up to 6 in (15 cm), usually smaller
- Aquarium: Shallow (12 in/30 cm), well-planted with floating plants; subdued lighting
- Water: 74-82°F (24-28°C), soft, slightly acidic
- Behavior: Peaceful, but avoid fin-nippers (barbs); tetras are suitable
- Diet: Prepared and live foods
Breeding: Requires deeper water (~6 in/15 cm) and temperature near 86°F (30°C). Males build large bubble nests; both parents collect eggs. Broods can exceed 1,000 fry. Large aquariums (≥40 in/100 cm) essential. Fry start on paramecium.
Dwarf Gourami (Colisa lalia)
The smallest and most colorful Colisa gourami, popular despite a tendency toward velvet disease.
Care essentials:
- Size: Up to 2.5 in (6 cm)
- Coloration: Males display alternating orange and sky-blue vertical bands; females silvery
- Water: 72-82°F (22-28°C), not overly strict, but dense planting important for nervous fish
- Behavior: Peaceful; form strong pair bonds
- Diet: Prepared foods (including vegetable matter)
Breeding: Males build bubble nests incorporating plant leaves (e.g., Riccia fluitans). Males may mate with multiple females sequentially. Fry are free-swimming in 3 days; remove adults to prevent predation.
Note: Hybrid color variants (sunset, neon) are often infertile.
Chocolate Gourami (Sphaerichthys osphronemoides)
A challenging species requiring precise water chemistry-dark, heavily vegetated conditions.
Care essentials:
- Size: Up to 1.8 in (5 cm)
- Aquarium: Heavily planted with subdued lighting; soft, acidic water (2-3 dGH, pH ~6.0)
- Plants: Cryptocoryne species (e.g., C. walkeri), Indian water star
- Water filtration: Must pass through peat
- Behavior: Peaceful and timid; avoid robust tank mates
- Diet: Live foods (may accept flake)
Breeding: Maternal mouthbrooder. Female collects and broods eggs in her mouth for ~2 weeks. Fry can be reared on brine shrimp nauplii, reaching 0.6 in (1.5 cm) in 3 weeks.
Other Notable Gouramis
Moonlight Gourami (Trichogaster microlepis): Silvery, orange chest markings; 79-86°F; shy; large, well-planted tank needed.
Spotted Gourami (Trichogaster trichopterus): Highly adaptable; 72-82°F; males build large bubble nests (up to 10 in/25 cm diameter); prolific, producing 1,000+ fry.
Snakeskin Gourami (Trichogaster pectoralis): Large (up to 8 in/20 cm); patterned body; 73-82°F; large, well-planted tank; peaceful but shy.
Thick-Lipped Gourami (Colisa labiosa): 2.3-4 in; peaceable males in separate breeding territories; nest can hold 600 eggs; requires stable temperature during egg development.
Honey Gourami (Colisa chuna): 2 in; vibrant orange-red males; highly territorial males; prone to velvet if stressed; 72-82°F, slightly acidic pH, dGH up to 15.
Croaking Gourami (Trichopsis vittatus): Up to 2.8 in; males produce distinctive croaking calls; soft, acidic water; floating plants for nest-building; 150 eggs per spawning.
Giant Gourami (Osphronemus goramy): Up to 28 in (70 cm); farms extensively across Asia; males build massive nests (20 in/50 cm diameter); spacious aquarium essential; will outgrow and eat tank mates; spawning can produce 20,000+ eggs.
Kissing Gourami (Helostoma temminckii): Up to 12 in, usually 6 in; natural silvery-gray or pink; "kissing" is dominance, not bonding; herbivorous, useful algae-grazers; 72-86°F; large tank (≥40 in/100 cm); breeding rare in aquariums; can produce 10,000+ eggs.
Paradise Fish and Related Species
Paradise Fish (Macropodus opercularis)
A hardy, robust species with striking coloration-one of the first fish bred in captivity.
Care essentials:
- Size: Males up to 4.75 in (12 cm), females smaller
- Coloration: Distinctive alternating orange-red and blue vertical bands; bluish gill spot
- Habitat range: Found from southern China to the Ryukyu islands; tolerates 50-95°F (10-35°C) in the wild
- Behavior: Males aggressive toward each other; spacious, well-planted tank essential
- Diet: Prepared and live foods
Breeding: Lower water level slightly and raise temp to ~82°F (28°C); increase live food. Males build bubble nests under floating plants. Females may lay 500 eggs; males guard brood. Infusoria required for fry. Warning: Hybridizes easily with close relatives (M. concolor, M. ocellatus).
Spike-Tailed Paradise Fish (Red-Eye Spiketail, Pseudosphromenus cupanus)
A smaller, peaceful paradise relative found in India and Sri Lanka.
Care essentials:
- Size: Up to 2.5 in (6 cm)
- Habitat: Slow streams, forest ditches, paddy fields; prefers darkness
- Aquarium: Dark substrate, retreats (bogwood), plants; 68-82°F (20-28°C)
- Behavior: Peaceful; keep only in pairs with gentle, unrelated species
- Diet: Omnivorous; prepared and live foods
Breeding: Increasing water temp and live food triggers spawning. Bubble nest may be under vegetation or in flowerpots. Fry hatch in 48 hours, free-swimming in 4 days. Both parents guard brood; no need to remove them.
Ornate Gourami (Malpulutta, Malpulutta kretseri)
A rare, delicate Sri Lankan species currently protected by government breeding programs.
Care essentials:
- Size: Up to 3.5 in (9 cm), typically <2.5 in
- Habitat: Dark, shaded forest waters (Kottawa Forest Reserve); soft, acidic
- Aquarium: Well-planted, delicate fish; effective filtration critical
- Water: 81°F (27°C); stable temp during breeding essential
- Diet: Small live foods and prepared diets
Breeding: Bubble nesters placing nests close to the tank floor (often under leaves). Both fish sink after spawning; female collects eggs, male guards. Hatching takes 2.5 days. Infusoria required for fry.
Climbing Perch and Bush Fish
These anabantoids differ from bubble-nesters, employing floating eggs or mouthbrooding strategies.
Climbing Perch (Walking Perch, Anabas testudineus)
The most adaptable anabantoid, capable of surviving outside water and "walking" to new pools.
Care essentials:
- Size: Up to 10 in (25 cm), usually smaller
- Habitat: Temporary pools, drainage channels, rice paddies; 59-86°F (15-30°C)
- Behavior: Can emerge on land and breathe air; primarily nocturnal
- Aquarium: Spacious, hardy plants, shallow water for breeding, covered (escape risk)
- Diet: Variety of foods; prefer live
Breeding: No bubble nest; eggs float to surface after mating. Remove breeding pair; eggs hatch in ~24 hours. Fry reared on infusoria. Young mature at ~4 in (12 cm).
Spotted Climbing Perch (Spotted Bush Fish, Leopard Ctenopoma, Ctenopoma acutirostre)
A small African ctenopoma with large eyes, indicating crepuscular (dusk-active) behavior.
Care essentials:
- Size: Up to 6 in (15 cm)
- Growth: Very slow, taking 3 years to reach adult size; usually sold small
- Water: 79-84°F (26-29°C), soft (2-4 dGH), neutral pH
- Aquarium: Subdued lighting, bogwood, retreats; shy
- Diet: Food tablets, fresh or processed live foods; will swallow small prey whole
- Behavior: Don't house with smaller fish (predatory)
Breeding: Bubble nesters. Little documented; males build nests. Frequent rotifers needed for rearing young.
Kingsley's Ctenopoma (Tailspot Bushfish, Ctenopoma kingsleyae)
A West African bush fish with variable coloration influenced by environment and age.
Care essentials:
- Size: Up to 5 in (12 cm), usually smaller
- Coloration: Dark slate-gray upper body, silvery underparts; juveniles have blackish tailspot ringed in gold
- Sexing: Males display "thorn fields" (spikes) behind eyes and at caudal base
- Water: Neutral pH, dGH up to 15, 77-82°F (25-28°C)
- Aquarium: Large, darkened substrate, well-planted with retreats
- Diet: Prepared and live foods
- Behavior: Predatory; don't mix with smaller companions as they grow
Breeding: Females produce thousands of eggs that drift upward among vegetation. Adults show no parental care and will eat spawn. Hatching ~24 hours; fry free-swimming in 48 hours. Black tailspot mark develops at 1 month; young fish more colorful than adults.
Other Notable Anabantoids
Combtail (Belontia signata): Sri Lankan; shy, retiring; pale yellowish-brown; males have longer dorsal fin; 74-82°F; subdued lighting; bubble nesters; both parents guard brood for 6 weeks.
Pikehead (Luciocephalus pulcher): Narrow, torpedo-shaped predator; 72-84°F; feeds exclusively on live invertebrates and small fish; species-only setup required; males brood eggs in mouth for 28 days; fry already 0.5 in (1.3 cm) at emergence.
Water Chemistry and Tank Setup Essentials
While each species has unique needs, several general principles apply:
- Temperature: Most prefer 72-86°F (22-30°C); always maintain precise range for breeding
- pH and hardness: Bettas and forest-stream species favor soft, slightly acidic water; gouramis are more adaptable
- Filtration: Essential for delicate species (chocolate gourami, ornate gourami); gentle flow recommended
- Floating plants: Nearly all species appreciate surface cover for nest-building and shelter
- Tank cover: Mandatory-most anabantoids jump or climb out
- Lighting: Subdued lighting preferred by shy, forest-dwelling species
- Substrate: Dark substrate replicates natural habitat and reduces stress
Common Health Considerations
Velvet disease (Oodinium): A parasitic infection affecting bettas (especially honey gouramis when stressed). Characterized by a gold or rust-colored dust on the body.
Fin damage: Avoid fin-nippers; some anabantoids (like bettas) have delicate fins requiring compatible tank mates.
Oxygen depletion: Although anabantoids breathe air, good water circulation reduces stress and prevents anaerobic bacterial growth in substrate.
Choosing Your Anabantoid
When selecting an anabantoid species:
- Aggression tolerance: Pair peaceful species (peaceful bettas, chocolate gouramis) with other gentle fish; keep aggressive males isolated or in species-only setups
- Space requirements: Giant gouramis and larger species need spacious tanks; small species can thrive in smaller volumes
- Water chemistry demands: Forest-stream and peat-swamp species (chocolate gourami, black betta) require soft, acidic conditions; others are forgiving
- Breeding goals: Bubble-nesters vs. mouthbrooders have different requirements; some species challenge even experienced breeders
- Availability: Rare species (ornate gourami) may require specialist breeders; common species (dwarf gourami, paradise fish) are widely available
Anabantoid fish offer incredible diversity, from the pugnacious Siamese fighting fish to the gentle peaceful betta and the specialized, delicate chocolate gourami. Understanding each species' specific needs ensures both fish and aquarist thrive together.
Frequently asked questions
What is a labyrinth organ and why do anabantoid fish have one?+
The labyrinth organ is a specialized, folded tissue structure in the head that allows anabantoid fish to extract oxygen directly from air. This adaptation lets them survive in stagnant, oxygen-poor waters like swamps, rice paddies, and ditches common in their native Asian and African habitats. All anabantoids must have regular access to the water surface to gulp air.
Can male bettas and other male anabantoids be housed together?+
No. Male Siamese fighting fish and many other anabantoids (male paradise fish, male honey gouramis) are highly territorial and aggressive toward other males. They will fight to the death in confined aquarium spaces. The exception is the peaceful betta (*Betta imbelis*), which can tolerate multiple males, though disputes may still occur near bubble nests. Always house aggressive males individually or in species-only setups.
Do all anabantoids build bubble nests?+
No. Most anabantoids are bubble-nesters (bettas, gouramis, paradise fish), but some species use alternative breeding strategies. Penang mouth-brooding bettas and chocolate gouramis are mouthbrooders, retaining eggs and fry in the male's or female's mouth. Climbing perch and some ctenopomas produce floating eggs with no parental nest-building. Research your specific species' breeding method before attempting to breed.
What water temperature do anabantoid fish need?+
Most anabantoids thrive between 72-86°F (22-30°C). However, specific species vary: Penang mouth-brooding bettas prefer 72-79°F; chocolate gouramis need exactly 81°F (27°C); paradise fish can tolerate extremes (50-95°F in the wild, though aquariums should maintain stable temps). Always check the precise temperature range for your species and provide a reliable heater.
Why must anabantoid aquariums have a cover?+
Nearly all anabantoids can jump out of water or climb through small gaps. Bettas are notorious jumpers, and species like slender bettas and climbing perch are equally prone to escape. A cover also maintains air temperature at the water surface, which is important for breeding and fry development. An uncovered tank risks fish loss.
What is the best first anabantoid for a beginner?+
Spotted gouramis (*Trichogaster trichopterus*) and paradise fish are hardy, adaptable choices. Dwarf gouramis are small and colorful but require careful monitoring for velvet disease. Male Siamese fighting fish can be kept singly but demand separate housing and careful tank mate selection. Avoid delicate species like chocolate gouramis and ornate gouramis unless you have experience with soft, acidic water chemistry.