2 liter soda bottle OR a gallon milk jug, both with the cap glued on. Bright orange duct tape wrapped around jug with my personal info written on it in sharpie (that's the law where I come from). 550 para cord for the leader (depth varies depending on how far down the bottom is - I always put my weights on the bottom). two granny knots about 2 inches apart 10ft off the bottom, with a swivel between them. tie a drop on there with about 2ft of 80lb mono with a mustad circle hook 6-8/0. repeat same knot,swivel, leader and hook about 4ft off the bottom. At the bottom use a 16oz solo cup filled with concrete and a small metal wire hoop in it to tie onto.
That's what I use on lakes for big cats. I put mine on either the edge of channels or on flats. Where really depends on water temps and shad locations. Heat of summer I go for ledges near deep water, spring i go for flats or shallows, but if shad ain't close by in either location then i start hunting for where they are.
2 liter soda bottle or even a milk jug will hold a pretty big fish. he may be able to pull it down, but he cant keep it down for more than a second or two. I also made up a some pool noodle jugs that I plan to try out soon.