Sterlet sturgeon

The sterlet is a small freshwater sturgeon in the family Acipenseridae, native to the large rivers and basins of the Black, Azov, and Caspian seas across Eastern Europe and Asia. It has the classic sturgeon form with a long snout, sensory barbels, rows of bony scutes along the body, and a shark-like tail; it is among the smaller sturgeon species. It is a peaceful, constantly swimming bottom-oriented fish requiring a great deal of space and cool, well-oxygenated water. Sterlets are pond fish rather than typical aquarium fish, needing a large pond with strong filtration and high oxygen; they are unsuited to warm, planted tropical tanks. They are carnivores feeding on invertebrates and sinking foods, and require specialized sinking sturgeon diets. Their long lifespan, large space needs, and cool-water requirements make them a commitment for dedicated pond keepers rather than casual aquarists.