yes you should inspect your nucs
chalkbrood is usually self limiting. warmer and drier weather will usually make it go away. not always. some few hives seem not to be able to overcome it and it can reduce brood survival to the point that the hive fails. this is not common.
chalkbrood is cause by a fungus. to the extent that you can reduce the conditions friendly to fungus, you can reduce the chalkbrood. warm, dry, and ventilated conditions are best.
requeening has often been advised. i am not sure i understand that logic except to get a young queen in there that can out lay the brood loss from chalkbrood.
i have had a number of hives with chalkbrood. with one exception, all have done fine.