If you give them a drop of water a day and they have candy and the attendants are still alive, they will last about a week or two. Then you need to replace the attendants. Then they will last another couple of weeks. Another option is put the cages in a box with some air slits and shake in a few bees and put some candy in and give them a few drops of water a day. If you replace the workers every couple of weeks you can do this indefinitely.