What size hyper split,solid and treble hook on 250 fall jigs

As big as you can get those fish to eat. A 12/0 hook wouldn't be too big as far as the split rings I forget the number 10/0 but be careful the stainless split Rings tend to open and stay open a little I would hate to lose a fish cuz it worked its way off the split ring.

Bluefin tuna

Depends for what