One of the most popular and beautiful koi in the world. White, red and yellow are the three original colors of koi fish. Over time that changed and now there is a much larger variety available. The Asagi koi are primarily blue with a diamond or fish net pattern that wraps around the back of the koi and spans all the way to the tail. You can usually find accents of red on the pectoral fins, bottom, tail, gills and even sometimes the dorsal fin. Asagi koi are one of the oldest variations. Many different koi variations come from the selective crossbreeding of an Asagi breed.