The flatheads where I've been fishing have moved into about 15 to 20 feet of water ( channel depth ). We went out last Sat night ( yes, it was cold ) and the bite was a little slow. Caught some channel cats about 4 to 5 lbs and two flatheads plus a couple missed hooksets. The water temp's about 75 give or take. We were marking a lot of fish in the creek channel over the last few days so we set up in a cove adjacent to the deeper water. I got a 43 lber on a big golden shiner and my buddy caught a 20 lber about 30 min later on blue gill. We left about 5 AM, happy to be in some heat.