The Blue Gourami (Trichogaster Trichopterus), also known as the Three Spot Gourami is common exotic fish which originates from the Southeast Asia and the northern island of Australia.
Blue Gurami shows a special breathing system. It lives in poor waters in oxygen, swamps and in areas cultivated with rice, and has developed a special breathing system called labyrinth. This is a highly vascularized organ, made up of bone blades, which allow for the assimilation of atmospheric air in addition to the gills. This adaptation in a difficult, oxygen-poor environment also resulted in a different reproduction behavior – the building of a bubble nest floating on the surface of the water to provide the oxygen needed for the eggs.
It is worth mentioning that Trichogaster trichopterus is very similar to Trichogaster leeri: the oval body, elongated and slightly flattened laterally. The anal fin starts from the gills and reaches to the caudal peduncle. The pectoral fins are filiform, thin, elongated and are reduced to some “strands”. They are tactile organs that allow the fish to detect obstacles in a water where visibility is low and to find food; they also have an important role in recognizing their partner or an enemy. The blue gourami can reach a body length of 15 cm in aquariums, the female being a little smaller. In nature, they can even reach 20 cm.
Aquarium and keeping conditions
Keeping this fish often proves to be difficult, due it having a territorial character. Most people tend to keep blue gourami in aquariums smaller than 100 liters, which is not recommended for the well-being of the fish. They require aquariums that are larger than 200 liters, where they can grow and develop well.
The height of the water column is less important. What is to be considered is the length and width of the aquarium. It is recommended to have at least 1 meter long and width for a couple. The aquarium must have a lot of surface plants to mimic its natural habitat. Freshwater aquarium plants like Ceratopteris provide shelter because the fish spends most of the time in the upper part of the aquarium. From a morphological point of view, this predisposition is visible through the mouth shape, oriented upward.
They do not need strong filtration, and the water jet does not have to create strong currents at the surface of the water.
The optimum temperature is around 25 °C, and the summer can climb smoothly to 30 °C.
Trichogaster trichopterus does not have special needs when it comes to the quality of the water, which in its natural environment can be sweet, neutral, acidic or hard. For reproduction, however, water with values less than 10 °GH is required to prevent problems in the development of the fry.
General description of Blue Gourami
If the young gourami are very active, the mature ones are quite lazy. Their behavior is generally peaceful and it is preferred that they are kept in pairs. Males do stand each other and the dominating ones risk being permanently chased, which will lead to delays in development and injuries. Females can be kept together without any major problems, they tend to be aggressive to one another but it does not post any serious problems. They are tolerant with other species, which they often ignore. It is an ideal fish for community tank where it can coexist with other gourami fish, if we provide enough space to delimitate their territories. The blue gourami does not appreciate larger fish or small and active ones such as Barbus tetrazona and Hypbessobrycon callistus which have the tendency to bite their fins.
Blue gouramis are sedentary fish. Once mature, they do not like the sudden changes in the aquarium environment. The same thing happens with the fry, which are quite fragile until they reach a length of about 5 cm.
They can eat almost anything from commercial fish food to artemia and grindal worms. They do require to be fed at least twice a week with vegetables (green lettuce or cucumber) because their digestive tract is longer than of other fish of the same size.
Sexing and breeding behaviour
Sexual dysmorphism is easy to observe, but less noticeable in young individuals. The male dorsal swimmer is more developed and sharp. The females are short and round. The female generally has less accentuated color, and the abdomen rounds as the ovarian mass develops, while the male remains slim.
Reproduction is relatively easy. An 80l aquarium is enough for spawning. The couple must be about one year old and a body length between 7-9 cm.
Water quality is not very important, but it is preferable to have water that has not been filtered for a couple of weeks and that has a lower hardness. The temperature will be between 25-28 °C. The aquarium must be covered to maintain a warm and humid atmosphere above the water. To avoid partial destruction of the nest due to drops that form during condensation process, it is good to have the glass cover at a slight angle. Filter and aeration of the aquarium are not mandatory, but a small external filter, set at minimum, will remove the bacterial pinnacle that forms on the surface of the water.
The aquarium must be well planted, and must have hideouts (flower pots, coconut shells, decorations from pet shops) for the female to use when she is overwhelmed by the male.
The male will start forming a bubble nest on the surface of the water where the future eggs will be kept until hatching. This is just like betta fish. The breeding process consists of the male courting the female, seducing her and bringing her under the bubble nest where they will start embracing and the female releases the eggs which the male will collect using its mouth and deposit them in the bubble nest.
The fry will hatch in about 36 hours and they will stay in the bubble nest or they will attach to the aquarium wall. At the age of 3 days they will begin to swim freely. It is recommended to remove the male from the aquarium because it may eat the young ones, thou sometimes it simply ignores them, only eating the ones that are dead or sick.
The fry will grow fast if they have enough space, a rich and varied diet and clean water, which we will renew about 10% every day.