Koi, originally named Nishikigoi in Japan, are carp with outstanding markings and color. They consist of many different varieties all of which have different names and descriptions. Along with their overall majestic presence, they will be the absolute center of attention on your property. They can grow up to 24 to 36 inches and live up to 60 years. According to Japanese breeder opinion, the largest Koi ever was measured at 41 inches. Because of their size, as well as their desire to live comfortably and healthy, they should be given the right pond to live in and are well worth the investment.