Hikari Wheat-Germ Formula Medium 2kg Hikari Wheat-Germ Formula is a high-quality, scientifically formulated, basic diet for Koi and Goldfish. This highly digestible, daily use, maintenance food, is recommend for use in cooler weather. Available as mini (3.5-4mm), medium (5-5.5mm) and large pellets (8-9mm), in a variation of 500g, 2kg & 5kg bags. Please select the required size from the drop down menu.