dominant male bitterling in bright spawning coloration, oak leaf litter on sand bottom, wild caught freshwater fish

adult amarus animal aqua aquadesign aquarium aquatic behaviour biotic biotope bitterling breeding captive clear closeup coldwater conditions controlled cyprinidae decorative domesticated driftwood ecology ecosystem endemic european explore fauna fish fishkeeping free hobby ichthyology interaction line local look nano native natural nature peaceful planted protection research rhodeus sensitive space spawn tank temperate threat underwater unusual water widespread wildlife