Fat Sleeper Angler

I found that Skysong Lake (around the Throne of the Elements with handy flightpoint!) has good pool regeneration so you can get your fish and work on guild achievements at the same time. The only problem is those accursed eels HATE rafts. Had to beat a Moray to death with my fishing rod, it wasn't pretty.

can be caught in inland [zone=6755] (where on map)
criteria of Draenor Angler
full guide

Go to Nagrand map, you can find and fish schools everywhere in the rivers and lakes but not in coast.
Two big problems here. One is that there are a lot of water mobs that will attack you and will make you "dismount" from your raft, like [npc=83739] because they autodamage you with [spell=161640] when you damage em. Second problem is that all the map rivers and lakes is full of bridges and falls and that will make you "dismount" from your raft too.

Best zone i have found is up fom ancestral grounds, plenty of schools and is the biggest area where you can navigate and go from School to school neverending and without drop your [item=85500]. You dont need to carry anything special, no bait, no lure, no pole.
Just go there and fish in the schools, your achivement will be done in 30mins.

This is the zone, click for map

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