The image displays an underwater scene within a large freshwater aquarium tank, located at the Fluviário de Mora in Mora, Portugal

The image displays an underwater scene within a large freshwater aquarium tank, located at the Fluviário de Mora in Mora, Portugal. In the foreground and center, a large, dark-grey sturgeon with a distinct elongated snout and barbels is horizontally positioned, swimming from left to right. Its body exhibits a textured surface, and pectoral, pelvic, and caudal fins are visible. The tank floor is covered with a light-green, coarse gravel substrate. To the right, the head and anterior portion of a pale-brown, large-bodied carp-like fish are visible, facing the viewer directly. Its eye and mouth are clearly distinguishable. In the mid-ground, a cluster of dark, rounded river rocks forms a habitat structure on the gravel bed. Above and behind these rocks, several other fish of dark and lighter coloration, consistent with carp or barbel species, are present; one large, lighter-bodied fish swims horizontally in the upper left background, while a smaller, darker fish is positioned beneath it. A large, dark, possibly moss-covered rock formation is visible in the upper left background. A vertical transparent panel or structural element is present in the upper right background. The water throughout the tank appears clear, with ambient light illuminating the environment and fish. No human figures are present. The fish are observed swimming calmly within the exhibit.