There is small, medium and large bait. And then I have a subdivision of bulky. Which one does the fish want. Well, that is for you to go fishing and find out on the day you want to go. Normal pressure- go medium.
Low pressure go large.
Let me help you a little more. Small baits are Slider worms, french fries, little worms, etc. Medium baits are 7 inch worms. Large baits are 10 to 16 inch worms. A small bulky bait would be a crawfish type lure.