Do you buy a spool of floro, or is there special stuff that is designed for leaders?

I just use some flouro off the spool. However there is fluorocarbon that you can buy designated specifically for leaders.

Either/or If I use a leader on a spinning outfit I just use lighter flouro that may be spooled on another reel. For my flipping setup I am currently using a free sample of Tatsu which should last me a long time. I have only retied the leader twice this year. I have never used the "specific" flouro leader spools you can buy. I think that is primarily used on offshore aplications.

There is a difference between any line and it's leader counterpart. Leaders are more abrasion resistant and imo stiffer. The only time I use a floro leader is offshore fishing, but have pretty much gotten away from it as I don't see any more strikes than from a traditional leader. Offshore I always use leader material. Inshore I just cut my leaders from Ande or Big Game and freshwater I use 20# leftover pline floroclear. My freshwater leaders are heavier than most people use but using a loopknot there is no compromise in lure action and I save a lot lures on snags by using a heavier leader.