When & Why You Should Use a Fluorocarbon Leader

Written By: John Flanagan

Fluorocarbon is a must-have for anglers who need a low visibility leader, an abrasion-resistant leader, or when targeting certain fish species. In this guide, we'll cover when and why to use fluorocarbon so you can have a productive day on the water, whether pursuing bluefin tuna in the open ocean or chasing wary trout in small streams.

Characteristics of Fluorocarbon Leaders

Fluorocarbon is a dense, single-strand extruded fluoropolymer fishing line . Since it's denser than water, fluorocarbon sinks. It is also hard and abrasion-resistant. 

Because its light refraction index is nearly the same as water's, it is nearly invisible as a leader.

Fluorocarbon leader line has a slightly smaller diameter than a monofilament leader of the same strength.

Fluorocarbon is relatively stiff, has good knot strength, and stretches very little. Although it costs more than monofilament, it typically lasts longer because it doesn’t deteriorate when exposed to sunlight.

Fluorocarbon leader material has an extremely low moisture absorption rate and remains flexible over a wide temperature range, including temperatures below freezing.

Why Use Fluorocarbon Leaders - What are the Benefits?

Fluorocarbon leaders have numerous benefits. The major one is that they are almost invisible underwater. They are also thinner than a comparable-strength monofilament leader, which reduces their visibility even further.

• Another benefit is fluorocarbon’s hardness and abrasion resistance. It can resist breaking when it contacts or rubs against rough surfaces such as logs, rocks, pilings, or fish’s mouths.
• Fluorocarbon is denser than water and sinks much faster than monofilament. This is beneficial when fishing with sinking lures or baits.
• Potentially longer casts are possible with fluorocarbon due to its thinner diameter.
• Fluorocarbon’s inherent stiffness gives better action to some trolled baits.
• Low stretch (especially with long leaders) allows the angler to feel subtle strikes and gives overall better sensitivity.

For detailed information on what kind of fishing line to choose, check out Types of Fishing Line – How to Choose. 

When to Use Fluorocarbon Leaders

When should you use a fluorocarbon leader? To answer this question, consider the fishing conditions, the techniques you will use, and the targeted fish species.

When fishing in clear water. Clear water is the number one reason to use a fluorocarbon leader. Your leader stands out in crystal-clean water and isn’t camouflaged by murky or stained water. A fish’s ability to see a leader is amplified in calm and clear weather, especially when fishing in shallow water. In these conditions, it can be difficult to entice fish to strike, so you need to choose the least visible leader material available, fluorocarbon. 

When the target species is extra finicky or leader shy. Certain areas get a lot of fishing pressure, and the fish get incredibly wary. They will avoid any baits or lures that don’t appear natural. When fish are skittish and wary, you must minimize the visibility of your leader to make your presentation as lifelike as possible. A similar approach is necessary with fish that have exceptional eyesight. Tuna, bonefish, tarpon, trout, bass, and walleye are all known to have great vision and to be leader-shy when pressured.

When you need extra protection against cut-offs. When fishing in areas where your leader may rub up against rocks, kelp, pilings, logs, or any other structure, the hardness of fluorocarbon decreases your chances of getting cut off. 

When targeting toothy or rough-mouthed fish. Fishing for toothy fish is a balancing act regarding leader choice. Using wire leaders will nearly eliminate cut-offs, but you may not get any strikes. Utilizing fluorocarbon will get you more strikes and reduce the possibility of getting cut off. Additionally, fluorocarbon can prevent your leader from failing to fray when fighting rough-mouthed fish such as tuna, tarpon, and snook.

When using sinking or suspending lures. Being denser than water, a fluorocarbon leader sinks with a sinking or suspending lure. The lure doesn’t “drag” the leader down with it as it sinks, and as a result, the lure gets deep faster than it would with a monofilament leader. It also gives the lure a more natural sinking motion. Fluorocarbon leaders can improve a lure’s motion during the retrieve since the sinking action of fluorocarbon allows the lure to track horizontally through the water. For in-depth information on fluorocarbon leader length, check out bass fishing legend Mike Iaconelli’s article by clicking here.

When Fluorocarbon Leaders May Not Be the Best Choice

While fluorocarbon can be used as leader in almost any fishing situation, it is not always the best choice.

Consider using no leader, a monofilament leader, or a wire leader when fishing in:

• Murky or cloudy water or at night
• Areas with little or no structure
• Targeting fish species that are soft-mouthed
• Fishing in areas with little fishing pressure and the fish are not leader-shy
• Using very heavy leader material, fluorocarbon may be too stiff to tie.
• Targeting toothy species such as sharks, king mackerel, muskies, or bluefish that can bite through fluorocarbon and monofilament
• Fishing with top-water lures (the sinking action of fluorocarbon inhibits the lure’s action)
• Your fishing technique requires a leader with stretch and shock-absorbing capabilities.

Fluorocarbon Leader Recommendations

Saltwater

• Light Inshore & Offshore     
  o    Leader strength 15 to 25-pound test
  o    Species: calico bass, redfish, sea trout, small tuna, bonito, small cobia, small tarpon
  o    Recommendation: AFTCO Saiko Pro 20lb. 
  
• Heavy Inshore & Medium Duty Offshore
  o    Leader strength 30 to 50-pound test
  o    Species: larger tarpon, snook, tuna, mackerel, grouper, snapper
  o    Recommendation: AFTCO Saiko Pro 50lb.
  
• General Duty Offshore
  o    Leader strength 60 to 100-pound test
  o    Used for most offshore trolling and deep bottom fishing
  o    Species include large reef and pelagic fish: yellowtail, amberjack, cobia, dolphin, sailfish, tunas
  o    Recommendation: AFTCO Saiko Pro 80lb.
  
• Big Game Fishing
  o    Leader strength 130 to 400-pound test 
  o    Species: marlin, giant bluefin tuna, swordfish
  

Freshwater

• Leader strength 15 to 25-pound test
• Often used with heavy jigs and other large baits
• Species: bass, catfish, walleye, pike, salmon, trout
• Recommendation: AFTCO Saiko Pro 20lb.
  

Fluorocarbon has a place in everyone’s tackle box. You will be a more productive angler by understanding when and why to use fluorocarbon leaders and putting that knowledge into practice. It could make the difference between a slow day on the water and a memorable one.

Author's Profile: John Flanagan

John Flanagan writes about fishing, boating, business, and coastal lifestyle. A life-long fisherman, licensed captain and aficionado of all things coastal, he pursues his passions on the coastal waters of North Carolina. Learn more here.