Hikari® Gold® is a daily diet, built upon decades of koi breeding and showing experience to meet the nutritional needs of koi while offering that desirable Japanese form. Hikari® uses the highest grade of ingredients formulated in scientifically developed quantities to produce a diet that will bring the brilliant colors of your fish to life rapidly. Grain sizes: Small: 3.5 - 4.0 mm Medium: 5.0 - 5.5 mm Large: 8.0 - 9.0 mm