Licorice Gourami 'Sentang'

Licorice Gourami ‘Sentang’, Parosphromenus sp. ‘Sentang’, is a rare wild labyrinth fish from Indonesia associated with the Sentang region of Sumatra. Like other members of the genus Parosphromenus, it inhabits heavily shaded peat-swamp forests and extremely slow-moving blackwater streams where the substrate is covered with decomposing leaves, branches, roots, and other organic material. These habitats contain exceptionally soft, acidic, tannin-stained water and are among the most specialized freshwater environments in Southeast Asia.

Adult Licorice Gourami ‘Sentang’ typically reaches only about 1.5 inches in length. Despite its tiny size, mature males can be spectacular. The body is slender and dark brown to nearly black, crossed by lighter cream to tan horizontal striping that can become more or less pronounced depending on mood. During display, males darken dramatically and spread their ornate fins, revealing brilliant blue-green to turquoise iridescence contrasted by deep red, burgundy, and black coloration. The dorsal, anal, and caudal fins can appear almost jewel-like when fully extended, with metallic blue-green bands glowing against the darker fin membranes. Females are considerably more subdued, generally displaying brown, beige, and cream coloration, although their pattern can change dramatically during courtship and breeding.

A tank of at least 10 gallons is suitable for a pair or small group, although larger aquariums provide greater stability and make maintaining multiple territories easier. The aquarium should be heavily structured with driftwood, fine branches, leaf litter, caves, and dense plant cover. Small caves, overturned coconut shells, film canisters, or similar enclosed spaces provide important spawning territories. Floating plants help diffuse the lighting, and the aquarium should remain relatively dim. Water movement should be extremely gentle, and a tightly fitted lid helps maintain the warm, humid layer of air required by labyrinth fishes.

Water chemistry is critical for long-term success. Temperatures between 74 and 80 degrees Fahrenheit are appropriate, with very soft, acidic water strongly preferred. A pH between approximately 4.0 and 6.0 is ideal, with extremely low carbonate hardness and low conductivity. Reverse-osmosis water is often the easiest starting point for maintaining appropriate conditions. Leaf litter, peat, seed pods, and other botanicals can be used to introduce tannins and humic substances while recreating the dark blackwater conditions these fish naturally inhabit. Stability and excellent water quality are essential.

Licorice Gourami ‘Sentang’ is a micropredator and can be considerably more particular about food than common gouramis. In nature it feeds on tiny crustaceans, insect larvae, worms, and other minute aquatic invertebrates. Live foods such as baby brine shrimp, daphnia, grindal worms, mosquito larvae, and similar appropriately sized prey are ideal. Frozen foods may also be accepted, but many wild specimens are reluctant to recognize flakes or pellets as food. Aquarists should be prepared to provide live or frozen foods regularly.

Temperament is peaceful but territorial, particularly among males. Parosphromenus are not well suited to typical community aquariums because their small size, deliberate feeding behavior, and specialized water requirements allow more active fish to easily outcompete them. Licorice Gourami ‘Sentang’ is best maintained in a species-focused aquarium or alongside only extremely small, peaceful blackwater species that will not compete aggressively for food. Multiple males can sometimes be maintained together in larger, densely structured aquariums where each can establish its own territory.

Breeding is possible under appropriate blackwater conditions and is one of the most fascinating aspects of keeping Parosphromenus. Pairs typically spawn inside tiny caves or other enclosed spaces. The male establishes and defends the spawning site and tends the eggs, often maintaining a small bubble nest within the cave. After hatching, the larvae remain inside the spawning site until they become free-swimming. The fry are extremely small and initially require microscopic foods before progressing to newly hatched brine shrimp.

Parosphromenus sp. ‘Sentang’ is an exceptional fish for aquarists interested in rare Southeast Asian blackwater species. Its tiny size hides an extraordinary amount of color, with displaying males transforming from understated brown fish into brilliant combinations of turquoise, blue-green, crimson, and black. The Licorice Gourami ‘Sentang’ does require specialized water and feeding compared with common gouramis, but in a carefully maintained blackwater aquarium its coloration, courtship displays, and fascinating behavior make it an incredibly rewarding species.