Yes, mist the dragon a few times a day to let him drink... OR give him a bath everyother day and mist once on the odd days.
Roachs-
Dubias are good, discoids are great as well but they both cost a good bit to get started. Lobsters produce well but they can climb and are annoying( from experiance, do not get them.) Lateriosessdsdsdfsg( the red ones) - Very fast though. All in all if you can understand that stick with either Dubia or discoid.