As a general rule of thumb on all artificial lures, I like to use approximately 24 inches of fluorocarbon leader. I only change the length when I use live bait. I like to use a minimum of 40 inches when using live bait. The reason is that braided line which I use 99% of the time for inshore fishing is very visible and intrusive in the fishes world. It does not matter what the color of the braided line is. All colors and every brand are visible to fish. The fluorocarbon leader obviously is a lot less visible.
With an artificial you're always working it, where the lure is always way back trailing the braided line and the fluorocarbon leader. In other words the lure can never swim or move past the leader and get to the braided line. So shorter leader can be used. When fishing with live bait, if the bait is casted up into the mangroves or structure, the first thing the live bait does is swim out of the mangroves or structure past the fluorocarbon leader and in front of the very visible braided line. The fish you're targeting now can see the braided line and this can totally shut down the bite or keep the fish from ever biting.
On another note if your fluorocarbon leader gets scraped or nicked, it gets much more visible. So it needs to be changed.
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