For less then 20 dollars i would pick up a spool of Seaguar flurocarbon, and using it when fishing bait. I have heard reports from fishermen who fish on boats like the BUNNY CLARK that traditionaly fishes very deep water for cod, that flurocarbon can make a difference AT TIMES. It is something to have in your codfishing arsenal since it is relatively cheap, and can only add to catching fish.
By the way, flurocarbon is not invisible under water, but is much harder for a fish to see due to its refracting light much differently then monofilaments.
EC NEWELL MAN*