Common nase

The common nase is a large, streamlined European cyprinid built for life in fast-flowing, well-oxygenated rivers. Native to the Danube, Rhine and other central European drainages, it is a rheophilic, cool-water fish that thrives at 10-20 C and does poorly in warm, still tanks. Its distinctive underslung, hard-lipped mouth is adapted to scraping algae and biofilm (aufwuchs) from rocks and gravel, and a proper diet should be predominantly plant-based with algae wafers, blanched vegetables and some invertebrate matter. Highly gregarious, it must be kept in shoals of six or more in a very large aquarium or, more realistically, a pond or river tank with strong current, clean neutral-to-hard water and stony substrate. Peaceful toward other species but demanding in space and flow, it is best suited to advanced, cold-water specialists rather than the general community aquarium.