Quote Originally Posted by Lyrinn View Post
.... Is it trial and error where you use every single bait at every single location?
Not really. Some is plainly marked lakes, rivers, coastline, etc. Some even are marked for stuff like bottom or insect feeders. Beyond that its what do you want to catch? Mooching you use the lowest level bait your target fish will bite on. Isolating a particular fish is the T&E part.

Also I find the notes on the fish entries in http://xivdb.com/ QUITE helpful.