Sera Koi All Seasons Probiotic food is an innovative food suitable for feeding adult koi any time of year, when water is above 46 degrees F of course. Along with the standard all season food ingredients (MOS, beta glucanes, Heamatococcus, and spirulina), this floating food also contains Bacilus subtilis, a probiotic. The probiotic supports healthy gut bacteria which in turn increases the immune system, and growth rate of the fish. This new food can be used weekly in place of season specific food, or it is also suitable as a staple food by itself.