Ultra Balance All-Season Koi Growth Diet - Medium Pellet 5 Lb Ultra Balance Premium Koi Food is simply the best for the growth, health, and performance of koi. Ultra Balance Premium Growth is formulated for optimum growth of young fish when water temperatures 64 F and above. It is a complete, nutritionally balanced diet providing the 5 key nutrients for optimal growth, health, and performance of your koi when fed as directed. Medium pellet is approx. 4.5 mm