Choosing the correct fishing line is of fundamental importance in the sport of fly-fishing. By reading a river fly-fishermen are able to determine if the fish are feeding at the waters surfacewhere floating lines are utilizedor deeper inside the river current and even on the river bedwhen a sinking line is required.
Artificial, nearly weightless flies are attached at the end of a fishing line. This may be a dry fly, wet fly, or streamer fly and their size is what determines the number classification of fishing line required. A fishing lines number, in turn, then determines the fly rods number.
When all of these parts are matched correctly they create a well balanced fly-fishing outfit.
If a fisherman intends to fish with a dry fly then a floating line is necessary. On the other hand, when using a wet fly, nymph, or streamer then a sinking line is required to help the fly imitate the sinking action of its real-life example.
Sinking lines sink at a predetermined rate of meters-per-second. A fast sinking line is used when a heavy river current requires that a line be sunk quickly. If a river is slow moving then a slow or medium speed sinking line is sufficient.
Because the fishing line is the fundamental actor, indeed the protagonist in the sport of fly-fishing, choosing the correct line of good quality is vitally important.