The Java loach (Pangio oblonga) is a popular, peaceful, eel-like freshwater fish known for its shy, nocturnal behavior and burrowing habits, often sold as the black or chocolate kuhli loach. Native to Southeast Asia, it thrives in planted aquariums with soft, sandy substrate and requires a group setting for security, enjoying hiding spots and a varied diet of sinking foods. They are hardy and can live up to ten years with proper care, but need a well-established tank to prevent stress. Appearance and behavior Body: Long, snake-like, with a uniform color from reddish-brown to black. Size: Grows to about 3-4 inches (8 cm). Behavior: Nocturnal, active at night, and known to "dance" or swim in circles, especially during water changes. They burrow in sand and hide in plants and driftwood. Social: Best kept in groups of 5 or more to feel secure. Aquarium care Tank Size: Minimum 20 gallons, but a longer tank is better for active swimming. Substrate: Fine sand or smooth gravel to protect their delicate bodies and barbels. Decor: Plenty of hiding spots like plants, driftwood, and caves. Water: Tropical, 75-85°F (24-29°C), pH 6.0-7.0, soft to medium hardness. Filtration: Good quality filtration is essential; they are sensitive to poor water quality. Lid: A secure lid is necessary as they can squeeze through small gaps. Diet Type: Omnivores. Food: Sinking pellets, bloodworms, brine shrimp, daphnia, and blanched vegetables. Snails: Will eat small snails, making them useful for pest control.
