We catch Grass carp off the surface I have caught them on a cereal called sugar puffs (UK) they are a honey covered puff wheat. They float so throw in a handful and then put 2 on a hook throw it out free line or use the rig I showed in my carp link
http://www.monsterfishkeepers.com/forums/showthread.php?t=28972
they love them also dog biscuit works well. its not a good picture but you can see the Ghost carp in my pond it stands out quite well.
