>>545138153
just buy out all the bait none of it makes that big a difference.
Auto-fishing trait from geniemon is tied to your fishing pole rarity. Lv 12 rod can auto-fish all purple fish. I haven't got the grandmaster rod yet so I can't comment on what it does but I assume it lets you auto-fish gold fish too. Probably not worth the 12k coins unless you've already bought out the rest of the stock of the store for the month because 1 minigame every 15 casts isn't a huge timesave but rod quality SEEMS like it has some impact on how big the fish you catch are too. Can't 100% confirm it just the feeling I get because I almost always catch max-size gold fish in icelake with the Lv 12 rod.
Icelake seems to have the best profits. Most valuable green fish, good value on gold fish & blue fish, worst value on purple fish
Sewers seems worst by a pretty wide margin
Purgatorio has decent value on all its fish but will make your computer try to catch on fire