serene garden waterfall with koi fish and lanterns in tranquil oasis. concept of zen, nature beauty, peaceful escape

waterfall koi garden tranquil oasis zen nature peace serenity meditative pond fish lanterns lush greenery stones water landscape reflection ambiance escape calm peaceful exotic decorative harmony japanese flora fauna elegant ornamental outdoor scenic natural aquatic fengshui environment botanical idyllic stillness sunlight vibrant cascade wildlife plant illumination retreat concept beauty ai generated