Mahachai Betta

Adults of this fish typically reach a length of 5 to 6 cm. Sexual dimorphism is clearly expressed: males are larger, their bodies are dark with turquoise speckles on the scales, and their fins and tail are adorned with characteristic streaks. Females, in contrast, are smaller and have a more modest gray coloration. It is worth noting that fish from different populations may have slight morphological variations; for example, the shape of the caudal fin varies from rounded to ovoid.

The roots of this species are found in Southeast Asia, specifically in Thailand. Its natural habitats are limited to areas around Bangkok, including the lower reaches of rivers flowing into the Gulf of Thailand. Unfortunately, many of these water bodies are located near a large city, and anthropogenic impact on them is very significant. Pollution has led to the complete disappearance of this species in many places where it once lived. It prefers to live in river mouths, estuaries, and brackish coastal swamps, often among Nypa fruticans mangrove thickets, where a dense network of roots provides shelter and food.

Males show competition for hierarchical position within the group, which sometimes leads to clashes. In small aquariums, it is recommended to keep one male with one or more females, as the latter are not prone to rivalry. They are peaceful towards other fish species. Due to their modest size, they can only be combined with small fish that can adapt to similar keeping conditions.

For keeping a single pair of fish, an aquarium of 40 liters or more will be optimal. It is important to provide shaded areas using a large number of floating plants or tall stem plants. Several shelters must also be provided; these can be natural snags or various decorative elements. If aesthetic appeal is not a priority, simpler options such as ceramic pots lying on their side or sections of PVC pipes will suffice. Unlike most of its relatives, the Mahachai Betta can live not only in fresh but also in brackish water with a salt concentration of 5–10 grams per liter. Notably, this species requires high hydrochemical parameters (pH / dGH), whereas other Bettas often prefer acidic, soft water. The key to successful keeping is maintaining a stable aquatic environment, achieved through regular aquarium maintenance and uninterrupted operation of the filtration system.

In their natural habitat, the diet of these fish consists of insects, small invertebrates, and zooplankton. Individuals adapted to aquarium conditions generally quickly get used to dry foods after recognizing them as edible. However, for complete nutrition, it is important to enrich their diet with protein-rich foods such as frozen and live foods – brine shrimp, daphnia, bloodworms – as well as specialized foods based on them.

When the breeding season arrives, the male begins to build a nest. It is a cluster of sticky bubbles, usually placed on the water's surface, in a corner of the aquarium, or under a floating leaf. After the nest is completed, courtship begins, resulting in the formation of a temporary pair. During the spawning process, the male and female come close, intertwining their bodies; at the climax, eggs are released and immediately fertilized. Each egg is carefully placed by the male into a separate bubble within the nest. After this, the female leaves the spawning site, and the male remains to guard the clutch. The incubation period lasts from 24 to 48 hours, and the hatched fry remain in the nest for another 3–4 days. Once they begin to swim independently, the male loses interest in them.

Most health problems in fish often arise from unsuitable keeping conditions. Maintaining a stable and comfortable habitat is a key factor for successful keeping. If symptoms of illness appear, the first step is to check the water quality. If deviations are found, it is important to take immediate measures to eliminate them. If the symptoms do not disappear or worsen, medicinal treatment may be required.

When purchasing Betta mahachaiensis, it is important to ensure there are no external signs of disease: clean fins without signs of rot, no white spots or film on the body, clear eyes without cloudiness. A healthy fish should be active, curious about its surroundings, and not appear emaciated. Avoid individuals that constantly lie on the bottom or near the surface, breathe heavily, or have an unnaturally swollen abdomen. Given the rarity of the species, ask the seller about the fish's origin: preference should be given to captive-bred individuals, as wild-caught specimens can be greatly weakened by capture and transport. In the store, pay attention to the keeping conditions: the presence of a lid on the aquarium is critical, as this species is prone to jumping. Also, check for compatibility with tank mates, as males can show pronounced aggression in cramped conditions.