

The giant gourami, Osphronemus goramy, is a species of gourami that is primarily native to Southeast Asia, notably from Indonesia (but limited to Sumatra, Java, and Borneo), the Malay Peninsula, Thailand, and the Mekong basin. The other three species belonging to the family are O. exodon from the Mekong basin and O. laticlavius and O. septemfasciatus from Borneo’s island. Giant gourami is commercially important as a food fish and is also farmed. It can also be found in the aquarium trade. The species has also been used for weed control, as it can be a voracious herbivore.
Commonly found in slow water (lentic) or permanent waters, including lowland lakes, ponds, and swamps, in addition to large rivers. Often found under dense aquatic vegetation, it migrates to flooded forests. Giant gourami can reach a remarkable size (>70 cm), but usually, the maximum length is 45-50 cm.
Adult size: 70 cm (common 45 cm) • Life expectancy: 15 years +

Features of this gourami fish species have two reasons.
1. respiratory organ (labyrinth organ), which enables it to gobble up oxygen into the air above the surface directly.
2. ventral fin (pelvic fin) to develop a long line like shrimp for the food fumble groundwater.
It lives in fresh or brackish water, particularly in slow-moving areas such as swamps, lakes, and large rivers. It is capable of breathing moist air, so can survive out of water for long periods. It is much larger than most gouramis, growing to a maximum length of 70 cm (28 in), it can grow up to 50 cm, weight 10 kg in Aquarium. In color, it is a pale to golden yellow, with silvery, pale blue stripes running vertically along its body. Females can be identified by their thicker lips. Giant gouramis build nests using weeds and twigs.

Usually, they are sold small, and often the aquarist does not have information on the size that this species reaches, creating erroneously in small aquariums.
When young, they have a pointed snout, a flat head, and an attractive color with stripes in shades of blue and silver / gray with a golden/yellow background. As they get older, they lose their lines and have a darker and less striking color. Adult specimens can develop a bulge above the eyes and have thick lips, the latter characteristic most evident in adult females.
Because it is a voracious herbivore, it is commonly used for weed control in some regions and is an important commercial species being widely cultivated for food purposes.
Eventually, you can go to brackish water. However, you spend most of your time in freshwater. It is the largest Gourami in existence and can easily reach 50 cm in 4 years or less.
This species can breathe atmospheric air, thanks to organs called the labyrinth. A modification forms this organ in the first branchial arch, highly vascularized and richly irrigated by blood vessels, which causes air to pass very close to the bloodstream, providing the exchange of oxygen with the blood through diffusion. The organ structure varies in complexity between species, tending to be more developed in specimens that live in an oxygen-deprived environment. This feature allows it to survive in oxygen-poor and stagnant waters for long periods.

Environment & water parameters
Freshwater, brackish water
• pH: 6.6 – 8.0
• Hardness: 5-25
• Temperature: 20 ° C – 30 ° C
The Giant Gourami is an egg layer and the male will build a bubble-nest before spawning. The male and female are distinguished by the dorsal fins and body color. The dorsal fin on the male ends in a point and the body is darker, changing to nearly black during spawning. When breeding, the water in the tank should be decreased to about 8 inches deep and the temperature should be 82°F. After spawning, the female should be removed to a separate tank because the male will jealously guard the eggs, sometimes becoming aggressive towards the female. The eggs will hatch in 24 hours.
Aquarium Maintenance & Behavior
The giant gourami is also popular in aquariums. Preferably, the tank should have a dark bottom, and densely planted edges, with room left in the tank’s center for them to swim.
Aquarium with minimum dimensions of 180 cm X 50 cm X 60 cm (540 liters) required. The choice of aquarium decoration is indifferent. Plants can be inserted, although they will eat the vast majority.
Its behavior in an aquarium is changeable, normally peaceful, with fish of the same size. It can become aggressive if kept in a small aquarium or with fish of similar shape. It is a very active and resistant species, being considered a fish of long duration when the well has taken care of. It can recognize its owner and has a unique personality.
Food
Giant gourami is Omnivorous (essentially herbivorous). It feeds mainly on algae, plants, and insects, secondarily to smaller fish in its natural environment. It will accept dry and live foods in captivity, and it should be provided primarily with plant-based eats, spirulina, and secondarily with live foods or fish fillets or shrimp.
Sexual dimorphism and reproduction
Oviparous. Spawning usually occurs between floating vegetation or a bubble nest made by the male for reproductive purposes. Eggs hatch in about 24-48 hours and fry swim freely after 2 or 3 days. Male protects offspring for a few days.
Sexual Dimorphism, Their dorsal fins, and body-color distinguish males and females. The male’s dorsal fin is pointed, while the female is slightly rounded. Male in breeding season changes color becoming quite dark.

Red Tail Giant gourami
Minimum Tank Size: 30 Gallons for Juvenile but 200 gallons prepare for Adult fish.
Care Level: Moderate
Temperament: Peaceful
Water Conditions: 22-27°C or 72-80° F , pH 6.0-7.5
Diet: Omnivore
Gourami tends towards herbivory, preferring algae-based foods, but will eat meaty foods. An algae-based flake food, along with freeze-dried bloodworms, tubifex, and brine shrimp, provides these fish with the proper nutrition while young. Once of significant size, they can be fed legumes, partially or fully cooked fibrous or starchy vegetables, or fruits.

Golden Giant gourami
Juvenile Abino Giant gourami
Adult Abino Giant gourami
same species: Osphromenus notatus, Osphromenus olfax, Trichopus satyrus, Trichopodus mentum, Osphronemus gouramy, Osphronemus gourami
Source: fao.org