i never use fluorocarbon as my main line but the few times i used it as leader material in 15-30lb test for saltwater species such as false albacore, weakfish, and fluke (summer flounder) i've always used a standard clinch or palomar and never had the knot fail.
i prefer mono or braid as my mainline bass fishing. i gave fluoro two shots and both times i had it knot up on me and would snap in random places