Aqua Master Color Enhancer Fish Food, 11-Pound/Bag, Small Enriched nucleotide enhances koi immunity High portion of Spirulina and Astaxanthin effectively enhances koi color richness Coated with Bacillus Subtilize natto to facilitate digestion and reduce water contamination Organic minerals effectively raise koi's vibrancy 12 Bags/carton;3.5-4.0 millimeter