Sewellia Sp. 'Sew03'

Datasheet

General Description

Sewellia Sp. 'Sew03' is a member of the Gastromyzontidae family within the Cypriniformes order. These fish have specialized morphological adaptations for life in fast-flowing waters, with a flattened body, compressed tail, and a unique pelvic valve formed by the last two pelvic-fin rays and a fleshy flap. They use a powerful sucking cup to cling to solid surfaces, as their ability to swim in open water is limited.

Aquarium Setup

For Sewellia Sp. 'Sew03', it is crucial to maintain a clean, well-oxygenated tank with a high turnover rate of 15-20 times per hour. An oversized filter and additional aeration are recommended. The use of aged driftwood and aquatic plants like Microsorum, Crinum, and Anubias spp. is beneficial. These fish should not be added to a biologically immature setup, and regular water changes are essential. The tank should have a tightly-fitting cover as these loaches can climb glass.

Behaviour

Sewellia Sp. 'Sew03' is not typically aggressive towards dissimilar-looking fishes but can be territorial, with some individuals more protective of their space, often a prime feeding spot. They exhibit dominance battles, usually in a belly-to-belly stance, with males generally being dominant. These loaches can be kept in groups of six or more to observe their natural behavior, with dominance hierarchies being less pronounced in larger groups.

Feeding and Diet

Their natural diet consists of benthic algae and associated microorganisms, supplemented with opportunistic intake of insect larvae. Homemade foods bound with gelatin and rich in fresh vegetables and Spirulina are recommended. A mature aquarium with ample algae-covered surfaces is beneficial for long-term success. Providing a separate tank to grow algae may be necessary if the main tank lacks sufficient algae due to herbivorous tankmates.

Reproduction & Dimorphism

Sewellia Sp. 'Sew03' is relatively easy to breed in captivity with the provision of suitable substrate and breeding conditions. Males exhibit soft, raised tubercles on their pectoral fins when sexually mature. Breeding can be triggered by temperature changes, and courtship involves elaborate behaviors such as circling and releasing eggs and milt into strong water flow. Fry require specialized diets like Infusoria and small live foods until they mature.

Habitat and Distribution

These loaches are primarily found in the shallow, fast-flowing, highly-oxygenated headwaters and tributaries of central Vietnam, specifically in Hue province. Their habitats consist of rocky substrates with minimal aquatic plant presence but rich biofilm development. Sewellia Sp. 'Sew03' is adapted to life in clear, oxygen-saturated waters commonly found in fast-flowing streams with riffles and runs. Other species co-inhabiting similar habitats include various Annamia, Balitora, Homaloptera, and other Sewellia species.