Deissner's Licorice Gourami

Adults of this fish reach a length of up to 4 cm. Their body is adorned with several wide horizontal stripes of dark and dull yellow hues. The fins, including the caudal fin, are broad and black, with noticeable blue markings. The intensity of these colors increases during the breeding season or when showing aggression. It is worth noting that such vibrant coloration is most often characteristic of males, while females appear less expressive.

Its natural habitat is Bangka Island in Indonesia, located east of Sumatra. Here it is found in small swampy bodies of water with rich aquatic vegetation, within the remnants of tropical forests. The area of these forests has significantly decreased due to intensive human economic activity, as the island is the world's largest tin producer.

Male Deissner's Licorice Gouramis show intolerance towards each other and engage in territorial conflicts, so keeping them together is not recommended. The ideal option is one male with several females. Peaceful cyprinids that can live in similar conditions are suitable as tank mates. Co-housing with closely related species, such as the Black Licorice Gourami, should be avoided to prevent possible hybrid offspring.

The optimal aquarium volume for a pair of these fish starts from 40 L. In terms of decor, it is important to create dense vegetation with rooted and floating plants, use a soft substrate, and provide various shelters. These can be driftwood, decorative elements (sunken ships, castles), or ceramic pots and vessels turned on their side. The latter often become spawning sites. Leaves and tree cones, such as alder, placed on the bottom not only complement the design but also recreate conditions characteristic of their natural habitat. During decomposition, they release tannins, which give the water a light brown tint and lower the pH level. Before use, leaves and cones must be dried, and then soaked in a separate container until they sink, and only then placed in the aquarium. They should be replaced every two weeks. To maintain the necessary hydrochemical parameters, it is recommended to use filters with peat filler. Aquarium equipment should be set up considering the fish's needs: a low light level and the absence of strong internal current are required. An important element is a tight lid, which prevents fish from jumping out and provides a warm, humid layer of air above the water surface, which is critical for the respiration of labyrinth fish. Aquarium care includes regular cleaning of the substrate from organic debris (excrement, uneaten food) and weekly water changes of 10–15% of the volume with fresh water.

The diet should primarily consist of live or frozen foods, such as bloodworms, Daphnia, and Artemia. Dry and freeze-dried foods can only be used as a supplement, although some breeders successfully accustom fish to them. Before purchasing, it is important to find out what Deissner's Licorice Gourami are fed at the pet store.

Spawning in these fish usually occurs in small caves (ceramic shelters will be useful here) or among fallen leaves. With the onset of the breeding season, the male chooses a spot and actively invites the female there, while simultaneously chasing away all competitors. He performs special ritual dances, swimming almost vertically head-down around the female and maximally fanning his fins. Once the female is ready, they swim into the shelter, where they lay up to 40 eggs, after which the female leaves the clutch. The male remains to protect the future offspring until the fry emerge from the shelter and begin to swim freely. If other fish species are present in the aquarium, the fry should be removed, as in such conditions, parental protection cannot be relied upon.

Most diseases are caused by unsuitable keeping conditions and poor-quality food. Upon detecting the first signs of illness, it is necessary to immediately check the water parameters (such as pH and dGH) and ensure the absence of high concentrations of dangerous substances (ammonia, nitrites, nitrates, etc.). The parameters should be brought back to normal only after this before proceeding with treatment. More detailed information on symptoms and treatment methods can be found in the section “Diseases of Aquarium Fish.”

When purchasing, extreme caution should be exercised, as other species of the genus are often sold under the name Parosphromenus deissneri in the pet trade, due to historical confusion in taxonomy. The true species is extremely rare in commercial sales. Healthy individuals should be active, have no visible fin damage, ulcers, or signs of emaciation. In store conditions, these fish often appear pale due to stress and unsuitable water parameters, but they should not show signs of heavy breathing or apathy. It is recommended to purchase only those individuals whose species identification has been confirmed by specialists, as incorrect identification makes it impossible to select a pair for breeding and maintain the purity of the line.