adult pair of gudgeon or bitterling fish in spawning coloration play in european lake biotope nature deisgn

acheilognathinae adult amarus animal aqua aquarium aquatic background beautiful behaviour biotic biotope bitterling blackwater clear coldwater coloration conditions controlled copy cyprinid dark decorative deisgn dwarf ecology endemic europe european fauna female fish fishkeeping free freshwater grey gudgeon ichthyology lake leaf leaves litter local look macro male natural nature oak ornamental pair play protection rhodeus river space spawn spawning spotlight tank temperate topmouth underwater vegetation water weed widespread wild