Shilo village is probably the fastest xp there is using perfectius fisher. I think barbarian fishing is the fastest xp overall but I don't know if that bot supports it.
Could try this, just set it so it powerfishes, dropping the fish. This way you'll make no profit, intact a loss but it's some of the fastest xp around.
Could try this, just set it so it powerfishes, dropping the fish. This way you'll make no profit, intact a loss but it's some of the fastest xp around.