stone moroko, wild aggressive dominant freshwater fish from east, captive adaptable coldwater omnivore, european river biotope

pseudorasbora parva topmouth gudgeon adult gobioninae cyprinid aquarium river asian invasion common widespread nature water clear curious natural aqua behaviour biotic animal aquatic harmful destructive fishkeeping underwater weed decorative closeup fish tank gravel native wild omnivorous predator sand ecology threat unusual fauna deathly aquadesign nano swim wildlife dangerous captive controlled conditions environment glass refraction