After years of trial and error, we’ve finally found the food that works best for our own koi – and this is it.Saki Hikari Multi Season is simply the finest koi food we’ve ever used. Premium Daily Diet for Koi – Ideal for Cooler Water Temperatures.
eBay
Viable bacteria are "living bacteria" that work in the intestines like bifidobacteria in yogurt, and "Saki Hikari" is rich in Hikari bacteria (a type of Bacillus). The Hikari bacterium added to Saki Hikari goldfish does not exist permanently in the intestine even if it enters the body once, but it is a transient bacterium that is replaced one after another.
eBay