Live bait for tarpons with threadfins. Circle or modified circle hooks are popular for this duty; most use short shank livebait hooks, 5/0 or thereabouts, in 2X or 3X strong. The main leader is four to five feet of 60-pound clear mono, the shock leader 12 inches of 100-pound-test fluorocarbon, chosen mostly because it's a lot harder than most monos and therefore more resistant to wear on the rough jaws of the fish.