Fresh herring is the best to use if you don't have the live ones. Frozen herring is too soft and mushy to keep on the hook. Is there a way of keeping dead herring usable for a period of time without freezing it?
take five lbs of herring and wash in fresh water then load bait into 48 qt cooler then fill with fresh water till bait is covered add 1/2 lb kosher salt and 1/3 cup clorox bleach, and ten lb bag of ice,stir the mix and let it sit for 24 hours and then pack in plastic bags and freeze.This will keep your bait from turning to mush.
Kosher salt 48" cooler with DRAIN
layer bottom with salt
then one layer of herring
another layer of salt over herring
repeat as above
the salt will pull the water from the herring and drain
will make the herring tuff
let sit/drain 24-36 hours
pat any remaining water from herring with paper towel
and freeze in ziploc bags or better yet vac sealer