The way fishing now works in is that once you click "Learn this skill" from the trainer you then have the capability to catch ANYWHERE in the world. You will only catch shitty things like weeds/tattered cloth/driftwood/etc until your skill is the appropriate level for that zone. If you cast in a pool you will catch anything that can be caught in that school regardless of skill level. So if you cast in the tastyfish pools at level one you can catch anything from tastyfish to keefers, to brownell blue tripped and dezien queenfish. The only difference is that the higher your skill is/ closer it is to the approptiate level, the faster you hook fish on casts