Key Item "Basket of Dafangshi" description states fish are "a favorite snack of the harutsuge" but should be "a favorite snack of the Kojin." The Dafangshi are an offering to the Kojin to restart the festival b/c so few Kojin can make it into Yanxia to obtain themselves. Harutsuge are the red fish you are trying to save -- they spawn and migrate in saltwater areas, and so likely never come into contact with Dafangshi living in the fresh water of the One River.