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Flathead catfish can reproduce at 18 in. For it to work, you should make every attempt to harvest them once they reach this size and provide only 3 to 4 spawning receptacles per acre. You want thirty 2 lb flatheads per acre not two 30 lb flathead per acre. Gizzard shad aren't really the natural prey of flat head but it might work in a shallow BOW. Tilapia would also probably be great for forage, particularly mossambica. Feeding some behind a net might introduce a lot of forage. I would complete forgo the crappie altogether. It's not clear, even without bluegill, bass, and crappie whether Flathead would recruit at the rate of 30 fish/acre per year. If they can, then this may be doable.
**Bump**
GSH would also be good prey, they require no nest tending to reproduce. Their mouths are also to small to eat fingerling flathead. Ideally, the only predators of the young should be other flatheads.
