About the Blue Gourami
Species Type: Freshwater Fish
Care Level: Easy. Does well in a slightly more narrow range of water parameters and shouldn't be used to cycle an aquarium. Will eat most prepared foods. May have some specific care requirements in terms of particular water parameters, social behaviors, food items etc.
Origin: Mekong River basin in China, Vietnam, Laos, Cambodia, Thailand, Myanmar and Malaysia. Live in lowland wetlands--still or sluggish water such as swamps, ponds, ditches, marshes, and flooded forest, always having thick vegetation.
Compatibility/Temperament: Reasonably peaceful with robust fish such as the quieter barbs, loaches, larger catfish. Males are territorial, becoming aggressive when ready to spawn. As the fish matures, some remain relatively peaceful while others become somewhat nasty to other fish. Best when kept in a male and female pair. Though they may be stated as compatible with Siamese fighting fish, this is highly dangerous to the fish, especially when the gourami and the fighting fish are both males.
A hardy and beautifully-coloured gourami, suitable for beginning aquarists provided the aquarium is spacious enough and the aggressiveness that is possible in this fish is borne in mind. This is a food fish in parts of its natural range.
Males are the larger sex and have a pointed dorsal and anal fin, while females are rounder and slightly smaller. Easy to spawn, this species builds a bubblenest among floating plants; up to 1200 eggs may be laid, and when spawning is completed the female will be chased away and should be removed to prevent injury. The male tends the nest, and he should be removed when the fry become free-swimming.
There are several colour variants available, giving this species several common names such as Opaline gourami, gold gourami, Cosby gourami, marbled gourami, and three-spot gourami. The latter is appropriate to the original form of this species, which is depicted in the first photo on the left above; the other photos depict some of the available variations. The dark spot at the base of the caudal fin is present in all variants.
This fish occurs in still plant-thick waters and should only be housed in well-planted aquaria with minimal water movement from the filter. Floating plants are important as the species, like all gourami, spends much time near the surface, browsing plant leaves and dangling roots for food. Floating plants also provide support for the bubblenest. Subdued lighting, partly achieved with floating plants, will calm the fish. It generally remains in the upper half of the aquarium.
In common with all the species in the suborder Anabantoidei, this fish possesses an auxiliary breathing organ called the labyrinth, named because of the maze-like arrangement of passages that allow the fish to extract oxygen from air taken in at the surface. The fish must use this accessory method, and it allows the fish to live in oxygen-poor muddy waters. To accommodate this, the aquarium must be kept covered to maintain warm moist air above the surface.
This species first appeared in the genus Sparus (without species name) in a 1764 paper by I.T. Koelreuter; its description by P.S. Pallas in 1770 placed it in the genus Labrus as Labrus trichopterus. Subsequently [date unknown to the writer] the genus changed to Trichopodus, the name from the Greek thrix (hair) and pous (foot); the current genus Trichogaster [see explanation below] comes from the Greek thrix (hair) and gaster (belly). Both names refer to the extended thread-like pelvic fins that have taste cells at the ends.
Until 1923, Trichogaster was used as the genus for the small gourami species and Trichopodus for the larger species. When the genus Trichopodus was established by Lacepede in 1801, it was not usual to designate a type species (as it is now), and later ichthyologists frequently designated one. A "type species" is the species that exhibits all the scientific characteristics for that genus, normally today the first such species to be described, and all species assigned to that genus will also share those characteristics. Topfer & Schindler (2009) detail the matter of the type species designations and errors respecting Trichogaster and Trichopodus; the end result was that in 1923, Dr. George S. Meyers incorrectly assumed the type species earlier assigned for Trichogaster and consequently established Trichogaster as the true genus in place of Trichopodus (which name became a synonym for Trichogaster) for the larger gourami species. Colisa was then selected as the genus for the small (dwarf) species previously assigned to Trichogaster.
This state remained (although in the literature there was frequent confusion) until 1997 when E. Derijst pointed out the error of the assumed type species by Meyers [see Topfer 2008]. R. Britz (2004) obsoleted the name Colisa, but its popularity continued in the literature. In 2008, J. Topfer thoroughly investigated the issue and recommended renaming of the species and K.-H. Rossmann (2008) followed. In 2009, Topfer & Schindler established Trichopodus as a currently valid genus of Osphronemidae, which includes the four large gourami species, Trichopodus trichopterus, T. leerii, T. microlepis and T. cantoris. The Colisa species reverted back to the genus Trichogaster as Trichogaster chuna, T. fasciata, T. labiosa, T. lalius, and T. bejeus. The species names of this genus were also corrected grammatically in accordance with the rules of the ICZN [Schindler 2009]. The California Academy of Sciences--Ichthyology [W.N. Eschmeyer] has adopted the afore-mentioned revisions.
Britz, R. (2004), "Why Colisa has become Trichogaster and Trichogaster is now Trichopodus," AAGB Labyrinth 136, pp. 8-9.
Derijst, E. (1997), "Nota over de geldigheid van de genusnamen: Trichogaster Bloch & Schneider, 1801; Trichopodus Lacepede, 1801; Polyacanthus Cuvier, 1829 en Colisa Cuvier, 1831 (Perciformes: Belontiidae)...," Aquarium Wereld 60 (9), pp. 217-236.
Rossmann, K.-H. (2008), "Neue Namen fur die Fadenfische?" Der Makropode [Zeitschrift der Internationale Gemeinschaft fur Labyrinthefische] 30(3), pp. 79-80.
Schindler, I. (2009), "On the spelling of the Species name of the genus Trichogaster (formerly Colisa) and Trichopodus," Der Makropode 1/09.
Topfer, J. (2008), "Lacepede-2. Teil: Seine Labyrinthfischgattungen Osphronemus, Trichopodus und Macropodus sowie die Gultigkeit der Namen," Der Maropode 30(2), pp. 41-52.
Topfer, J. & Schindler, I. (2009), "On the type species of Trichopodus (Teleostei: Perciformes: Osphronemidae)," Vertebrate Zoology 59(1), pp. 49-51.
Blue Gourami Diet
An omnivore in its habitat eating insects, worms, crustaceans, algae and detritus, it will eat almost any prepared foods; for variety feed frozen daphnia and bloodworms, artemia, live worms and insects.
Attains six inches, though aquarium fish tend to be four to five inches.
Minimum Tank Suggestion
36 inches in length.
Ideal water parameters for Blue Gourami
Soft to moderately hard (3-30 dGH), acidic to basic (pH 5.5-8.0) water, temperature 24-28C/75-83F. Fish are likely to be commercially raised and adaptable to within the given parameters; wild-caught fish require soft, acidic water.