I’ve never had much luck catching monster flats in the daytime. I fish strictly at night and I fish only live bait. Monster flats will not travel for dead or cut bait. If you want small flats the use whatever. Bluegills work but I use big crappies and big bluegills if possible. I see a lot of comments recommending cut bait. I guess that’s fine for small flatheads. I guess I should clarify what I consider monster flats. 40, 50, 60 lbs and above. 30 and 40lb,ers medium id say. I’m 64 years old and have commercial fished from age 12 to 18 with my uncle in pool 11 on the Mississippi and fished here all my life. I know these fish. Ile also let you in on a little secret, there are flatheads in the Mississippi river a lot bigger than 60lbs