Feed with chum mixers and wait til they're around and confidently feeding then cast out. I found a great hookbait for such purposes by accident a few months back: when Woollies went bust many of their old stores are now B&M Homestores. They sell a few fishing bits and bobs including bait (bags of hemp, boiles, pellets etc). One thing they sell is a jar of floater baits, which is blown sweetcorn, scopex flavour. The grains are about the same size as a chum mixer, golden brown colour with nice scopex flavour, they are very light and good floaters and are very tough and stay on the hook - perfect for casting with a fly rod and the carp where I tried it took them straight away