Betta ideii "Wilas" (often referred to as Betta sp. Wilas) is a specific geographic variant of Betta ideii, a large and striking wild mouthbrooding betta from the unimaculata complex. Native to the freshwater streams of South Kalimantan, Borneo, these fish are prized by hobbyists for their unique appearance and relatively large size, reaching up to 3.3 inches (8.3 cm) in standard length. Key Characteristics of Betta ideii * Distinctive Marking: The species is most easily identified by a prominent orange or yellowish patch located between the front of the eye and the upper jaw, a feature that becomes particularly vivid in adults.* Mouthbrooding Behavior: Unlike the more common bubble-nesting Betta splendens, B. ideii is a paternal mouthbrooder. After spawning, the male carries the eggs in his mouth for approximately 10 to 14 days until they hatch into free-swimming fry.* Body and Coloration: They have a robust, fusiform body shape. While wild specimens often display earthy or dark brown tones, they can develop an iridescent sheen when comfortable or displaying. Large males can even appear nearly jet black when preserved or under certain lighting. [5, 6, 7, 8, 9, 10] Habitat and CareIn nature, these fish inhabit clear, slow-moving jungle streams that are often cool and shaded. To successfully keep them in an aquarium, the following conditions are recommended: [5, 11] * Water Parameters: They prefer slightly acidic to neutral water with a pH of 6.0 to 7.0 and temperatures between 25–28°C (77–82°F).* Aquarium Setup: A tank of at least 10 gallons is recommended for a pair, though larger is better due to their size and active nature. They appreciate plenty of hiding spots made from driftwood, rocks, or dense leaf litter to mimic their natural habitat.* Filtration: Slower-moving water is preferred; simple sponge filters are often the best choice to avoid strong currents that can stress the fish.
