My 5 or 6 saltwater lines all have 30"-40" (depending on the line) of 40lb test needle knotted to the fly line. I go through the center/core of the fly line about an inch before poking out for a 3 or 4 turn knot on the reel side of the hole. A drop of super glue and two thin coats of that smelly rubber cement stuff completes the task. I blood knot the 40lb to 30lb, again with a drop of glue. This works great for stripers and blues.