Use fluorocarbon fishing line to spool your entire reel, or just use it as a leader to your mono or braid filled spool. Fluorocarbon fishing line is non-porous which means it will sink in the water. It is very abrasion resistant, unlike braided fishing line. The best part about it is the fact that it is less visible to fish underwater than any other fishing line.
A lot of fishermen nowadays will use fluorocarbon as their leaders and braid as their main line. This gives you some great advantages while fishing. This gives you almost all of the advantages of braid as well as the fluorocarbon. The braid offers extra sensitivity and you can pack more line onto your reel. The fluorocarbon leader offers near invisibility and abrasion resistance. Using the fluoro as a leader can save you money as well. Don't get me wrong, using this line by itself is still a very good technique!