freshwater predator channel catfish, prussian carp and common perch rest in european temperate cold-water river biotope aqua

aggressive america animal aqua aquadesign aquarium aquatic barbel behaviour biotic biotope carassius carp cat catfish channel clear closeup coldwater common danger dangerous design driftwood ecology ecosystem european fauna fish fishkeeping fluviatilis freshwater gibelio gravel greedy grey group habit healthy ictaluridae ictalurus instinct invasion invasive juvenile live mouth natural nature north perca perch plants potamogeton predator prey prussian punctatus rest river sand substrate swim system tank temperate threat underwater voracious water widespread wild