When it comes to fly lines though, there are a few factors that you have to take into consideration.  First, you are going to want to ensure that you match the line weight up to the same weight fly rod you are using, to ensure a smooth balance.  Properly balancing the rod and reel will give you the best casting accuracy, while still providing you all day casting abilities and none of the fatigue and muscle stress that you normally feel, when using unbalanced fly rods.

photo credit: kasperbs

The fly fishing line weight is key to pulling in monster fish, as well as being able to get the line to properly unspool from the reel.  If the fly that you are using is too heavy, and the line that you are using is too light, you are going to have a hard time trying to bring any larger fish in, as well as being able to apply the pressure needed during the fight.  You run the risk of busting the line, and fly lines aren't cheap to replace.

The fly fishing line setup that you use is crucial to accurate casting, as well as being able to get the fish back onto the boat or bank.  As you can see, if you're using the wrong weighted fly line, matched up to a rod that it isn't suited for, you are going to wear down your muscles, wrist, and elbow, causing you discomfort while casting, as well as being unable to cast with the accuracy required to catch those spooky fish.  There are some days where you have to get the fly right on top of the fishes nose, and the only way to accomplish this is by using the proper fly fishing line setup.

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