I fish on the same lake most of the time. Deepest place on the lake is 22 feet in the middle with sides from 4 feet to 10. I fish mostly for bluegills and crappie. The best fishing I have found is in deep water with the fish from 0 to 6 feet. So I need a fish finder I can find these fish or the ones on the bottom in 10 feet of water. I fish from a 12 foot aluminum boat with a electric trolling motor on the back. Would like to stay under $600. Thanks for any help