Goldfish are one of the most popular pets in the world. Undoubtedly their brilliant metallic gold and reddish coloration is greatly responsible for that popularity. Their mild temperament, extreme hardiness, and lack of fussiness about food and water conditions also add to their appeal. A clean, well-cared for, and attraction decorated aquarium containing a few brightly colored goldfish swimming easily through plant thickets and around rock clusters is a fascinating and relaxing sight.