Bettas and gouramis

Bettas and gouramis are labyrinth fish: they breathe air at the surface and hold small territories, so temperament matters as much as water. Wild bettas and chocolate gouramis ask more of you than the pet-store standards. Profiles list tank size, temperament and conditions.

Tank size: 5–264 gal; 5 gal (20 L) to 264 gal (1,000 L); half the list needs 16 gal (60 L) or more
Temperature: 72–81°F; 22–27°C, most of the list
pH: 5.0–7.0; Most of the list
Difficulty: 17 easy; 65 medium · 49 difficult
Temperament: 52 peaceful; 70 mostly peaceful · 9 aggressive

131 species and 17 varieties

The family

One family that breathes air

Bettas, gouramis, paradise fish, licorice gouramis and the giant gouramis are one family, the Osphronemidae, and they share the labyrinth, a folded organ behind the gills that lets them gulp air at the surface. They live in warm, slow, often oxygen-poor water, so they want a still surface, floating cover and a lid that keeps a layer of warm, humid air over the tank. Most of them hold a small territory, which is why so many profiles say one male per tank. The gouramis, the paradise fish and the show betta build bubble nests, while most wild bettas and the chocolate gouramis are mouthbrooders. And the family runs from a licorice gourami under 1 inch (2.4 cm) to a giant gourami of 27.6 inches (70 cm), so read the adult size before anything else.

01
A labyrinth
Gulps air at the surface, so keep the surface still
02
Warm air above
A lid keeps the humid layer they breathe
03
One male
Most hold a territory and squabble with rivals
04
Nests or mouths
Bubble nesters and mouthbrooders in one family

Community

The ones that fit a community tank

The community gouramis are the easy end of the family, and the catalog marks most of them peaceful. The honey gourami stays at 2 inches (5 cm), lists 20 gallons (75 liters) and lives in a group of four to six with more females than males. The pearl gourami is the classic centerpiece for a 30 gallon (115 liter) planted tank at 4.7 inches (12 cm), and the moonlight gourami is a calmer, slower fish that lists the same tank. The croaking gourami and its threestripe cousin are small, quiet fish for 12 to 25 gallons (45 to 95 liters) that make an audible click when they display. The thick-lipped gourami is the sturdier choice at 3.5 inches (9 cm), and the spiketail paradisefish is a 2.6 inch (6.5 cm) fish for a 12 gallon (45 liter) tank with none of the paradise fish's temper. Keep all of them with fish that do not nip and do not crowd the surface.

Bettas

The betta side of the family

The show betta and its wild relatives are the other half of the list, and they have a page of their own. The fish in the shop is one species, Betta splendens, marked beginner and aggressive, kept one male to a tank in 7 gallons (25 liters) or more. Most of the wild species are mouthbrooders, calmer fish for a pair in a soft-water species tank. The crescent betta and the emerald betta are the wild cousins closest to the show fish, at 2.4 inches (6 cm) in 11 to 12 gallons (40 to 45 liters). The spotted betta is marked easy and the whiteseam betta stays at 1.2 inches (3 cm), both good first mouthbrooders, and the one-spot betta is the largest of the genus here at 4.5 inches (11.5 cm) with a 29 gallon (110 liter) minimum.

Blackwater

Licorice and chocolate gouramis are specialists

The licorice gouramis, the Parosphromenus, are marked difficult without exception. They stay between 0.9 and 1.6 inches (2.4 and 4 cm), list 5 to 11 gallons (20 to 40 liters), and want blackwater, which means very soft water at a pH around 4.5 to 6.0, leaf litter, dim light, live or frozen food and no other fish. Breeders keep them as pairs, and Harvey's licorice gourami is a threatened species that hobby breeding is helping to keep going. The chocolate gouramis are their larger cousins and mouthbrooders. The chocolate gourami itself is marked medium and wants heat, 79–88°F (26–31°C), while the crossband, sharpnose and Vaillant's chocolate gouramis are marked difficult, and the last is a shoaling fish for a group of six. The eyespot gourami is a tiny, cool-water mouthbrooder at 64–77°F (18–25°C) that also goes in a group.

Size and temper

Paradise fish, combtails, pikeheads and giants

The paradise fish is a hardy fish for an unheated tank at 50–72°F (10–22°C), 3.1 inches (8 cm) in 25 gallons (95 liters), but it is marked aggressive and one male per tank. The round-tail paradise fish is the easy, milder relative for 61–75°F (16–24°C), and the black paradise fish takes a heated tank. The combtail gourami reaches 4.7 inches (12 cm), lists 53 gallons (200 liters) and is marked aggressive and solitary. The pikeheads are ambush predators that eat anything that fits in the mouth, marked difficult and aggressive, so they live alone. The giant gourami reaches 27.6 inches (70 cm) and lists 125 gallons (475 liters), the giant red tail and seven-banded giant gouramis reach 19.7 inches (50 cm) and list 264 gallons (1,000 liters), and the snakeskin gourami is the peaceful big one at 9.8 inches (25 cm) for 61 gallons (230 liters).

By the numbers

Smallest

Largest

Easiest to keep

Most peaceful

Fits a 20 gallon tank

Fits a 30 gallon tank

FAQ

Common questions

Are bettas and gouramis related?

Yes. Both belong to the Osphronemidae, the labyrinth fish family, along with the paradise fish, the licorice and chocolate gouramis and the giant gouramis. They all breathe air from the surface through the labyrinth organ, and most of them hold a territory.

Can a betta live with a gourami?

Not safely. They are close relatives with the same body plan and the same claim on the surface, so they read each other as rivals. The show betta is marked aggressive in the catalog and shows no tank mate picks for that reason. Keep one labyrinth species per tank unless the tank is large and planted enough for the calmer gouramis to spread out.

Which gourami is the most peaceful?

The honey gourami, marked easy and peaceful and happy in a group. The pearl gourami, the croaking gouramis and the spiketail paradisefish carry the same marks. The dwarf gourami is peaceful toward other fish but not toward a second male.

What size tank do gouramis need?

From 12 gallons (45 liters) for the threestripe croaking gourami and the spiketail paradisefish, 16 gallons (60 liters) for a dwarf gourami, 20 gallons (75 liters) for honey and thick-lipped gouramis and 30 gallons (115 liters) for pearl, three spot and moonlight gouramis, up to 61 gallons (230 liters) for a snakeskin and 125 gallons (475 liters) for a giant gourami. The two other giants list 264 gallons (1,000 liters).

Do bettas and gouramis need a heater?

Most do, at roughly 72–82°F (22–28°C). The paradise fish is the exception, listed at 50–72°F (10–22°C) and better off without a heater, and the round-tail and Hong Kong paradise fish and the eyespot gourami also run cool. The chocolate gourami is the opposite and wants 79–88°F (26–31°C).

Why does my gourami keep going to the surface?

To breathe. Every fish on this page gulps air through its labyrinth organ, so a trip to the surface every few minutes is normal, and a fish that stays there gasping is the one to worry about. Keep the surface still, leave a gap of warm air under the lid and do not aim the filter outflow at the top of the tank.

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