Giant Gourami Care Guide - Size, Tank Setup & Breeding

The Giant Gourami is one of the largest gouramis kept in the aquarium trade, with a deep, laterally compressed body, a rounded head and thick, fleshy lips. Young fish are often brownish or grey with darker markings, while adults commonly develop a more uniform grey, olive or brown colouration. Their long dorsal and anal fins give the body an imposing profile, and older males may develop a noticeable forehead hump.

Despite its size, this species has the characteristic labyrinth organ of gouramis, allowing it to breathe atmospheric air. It is an intelligent, alert fish that often learns to recognise its keeper and may investigate activity outside the aquarium. Adults can be surprisingly personable, but they are powerful fish with strong appetites and considerable waste production.

In the wild, Giant Gouramis occupy warm, sluggish waters with abundant marginal and floating vegetation. They are capable of surviving in oxygen-poor habitats by rising to the surface for air, and their broad bodies and flexible feeding habits suit life in floodplain environments. They are also valued as food fish throughout much of their introduced and native range.

Although juveniles are sometimes sold as manageable community fish, they grow into exceptionally large adults. Their eventual size, strength and territorial behaviour make them a specialist species for very large public or purpose-built aquariums rather than ordinary home tanks.

The Giant Gourami is native to freshwater habitats across mainland Southeast Asia, including Indonesia, Malaysia, Thailand and Cambodia. It inhabits slow-moving rivers, floodplain waters, swamps, ponds and other heavily vegetated environments, and it has also been widely introduced beyond its native range for food production.

An adult Giant Gourami needs at least a 2,000-litre aquarium, and substantially larger facilities are preferable; a practical footprint should be around 300 × 100 cm or more, with enough depth and swimming length for a fish approaching 70 cm. Use a strong, tightly secured cover because this species can surface-breathe and may push against equipment or lids. Provide open swimming space, sturdy marginal or floating vegetation, robust wood and smooth structures, while avoiding fragile plants and sharp décor. Use powerful biological and mechanical filtration with good circulation, but leave calmer areas near the surface. A bare or fine-sand substrate is easiest to maintain and prevents injury during feeding or movement.

Up to 70 cm (28 in) in total length in exceptional adults. Males are generally larger and more heavily built than females.

Giant Gouramis are omnivorous and feed on plant matter, fruits, seeds, insects, crustaceans and smaller aquatic animals. Offer a high-quality large-pellet or soft omnivore diet supplemented with vegetables such as peas, leafy greens and courgette, along with occasional prawns, earthworms, insects or other meaty foods. Young fish need frequent nutritious meals for rapid growth, while adults benefit from a varied diet with plant foods forming a substantial proportion. Avoid relying on fatty mammal or bird meat.

Only exceptionally large, robust fish should be considered as tankmates, such as mature large cichlids, giant catfish, large pacu or other powerful species with compatible water requirements. Even these combinations require careful observation and a very spacious aquarium. Small fish, shrimp, snails and delicate or slow-moving tankmates may be eaten or injured, while multiple Giant Gouramis can become aggressive as they mature, particularly in confined quarters. Keeping one specimen is often the safest arrangement unless a truly enormous system is available.

Giant Gouramis are bubble-nest breeders. A mature male constructs a floating nest among vegetation, often incorporating plant fragments, then courts the female beneath it. After spawning, the buoyant eggs rise into the nest, where the male usually guards them and tends the young. Provide a very large, quiet breeding aquarium with floating cover and gentle filtration; the female may need to be removed if the male becomes aggressive. The eggs generally hatch within a few days, and the fry require suitably fine foods as they develop.

Males usually grow larger and develop a broader head, thicker lips and a more pronounced nuchal hump as they mature. Females tend to have a rounder, fuller body, while their forehead profile is less strongly developed; visual differences can remain subtle in young fish.