Acanthocobitis urophthalmus

Adults reach a length of approximately 4 cm. Their body is elongated and slender, with rather short fins. The pelvic and pectoral fins are primarily used by the fish to move along the bottom or to "stand" on it, rather than for active swimming. The fish's mouth is surrounded by sensitive barbels, and its coloration is a combination of dark and light yellowish stripes, creating an effect reminiscent of a tiger pattern.

The species is endemic to the southwestern part of Sri Lanka, where it primarily inhabits lowland rivers such as the Kelani and Nilwala. These fish prefer areas with shallow water, fast currents, and a bottom covered with pebbles, sand, or a mixture of stones and plant detritus. In their natural habitat, the water is highly oxygenated.

Within their own species, relationships are based on territorial competition. Although Acanthocobitis urophthalmus needs the presence of conspecifics, they prefer to keep to themselves, each occupying their own small area on the bottom. If there is insufficient free space, skirmishes may occur. Towards other species, the fish are peaceful. They get along well with most fish of comparable size. Excellent tankmates would be species that inhabit the water column or near the surface.

For a group of 3–4 Acanthocobitis urophthalmus, the optimal aquarium volume starts from 50 liters. When setting up the tank, primary attention should be paid to the bottom layer. These fish like to dig in the substrate, so sand, fine pebbles, and aquarium soil are desirable as substrate. It is important to provide hiding places for each fish on the bottom, such as individual snags, coconut shells, thickets of rooted plants, or other natural and artificial elements. The presence of an internal current is recommended; usually, a separate pump is not required for this, as an internal or external filtration system successfully provides not only water purification but also sufficient circulation. Acanthocobitis urophthalmus prefers soft, slightly acidic water. For long-term well-being, it is important to maintain hydrochemical parameters within acceptable limits and avoid sharp fluctuations, such as pH and dGH.

In their natural habitat, the fish's diet consists of small invertebrates and detritus. In home aquariums, they readily accept most popular sinking foods of appropriate size, including flakes and granules.

Reliable information about successful breeding in aquarium conditions is absent. In nature, the fish spawn in flowing waters, but the specific conditions for stimulating spawning in captivity have not yet been studied. Breeding attempts require creating conditions that maximally imitate natural mountain streams with intense aeration and high-quality filtration.

The species is sensitive to poor water quality and the accumulation of organic waste, which often leads to weakened immunity and the development of secondary bacterial or fungal infections. Characteristic signs of illness include refusal to eat, apathy, body film, rapid breathing, or fin damage. Prevention involves maintaining stable environmental parameters, regular water changes, and powerful filtration.

When selecting specimens, attention should be paid to the following signs:

• fish activity and absence of signs of apathy
• intact fins and absence of visible ulcers or spots on the body
• normal breathing without signs of rapid gill cover movement
• good body condition, excluding severely sunken flanks

It should be noted that fish of this species often arrive for sale after transport, so it is important to ensure the absence of stress behavior and the cleanliness of the water in the seller's aquarium.