i would fish smaller and slower. small shiners or leaches around 2" so that you are kinda matching the hatch. ive seen guys using mayfly nymph imitations with success. personally i like a black 2in curly tail and as light of a lead head i can get away with. also fish the shiners or leaches on a slip bobber rig around 2ft from the bottom. when the walleyes are on bugs you have to fish slow they don't want to chase down their prey when they can just leisurely pick them off.