The Red Swamp Crayfish are what are typically used for "crawfish boils" and are available in 50#-60# sacks. They will burrow into the pond banks.

What Bill is alluding to when he talks about cover is 110% correct, typically you want to have 25% of the surface area of the pond in cover for the fish. Once you start doing the math for artificial cover, that gets either very expensive or very time intensive very quickly. For your pond you would need to add approximately 7,600 sq. ft. of cover for the fish. A single stack of pallets is only 16 sq. ft. Cover needs to be of different sizes and at varying depths, large fish will utilize cover with more open spaces in it vs. small fish that will utilize dense cover with small spaces.