With a strong enough flow you do not have to feed syrup. To bait them up in your situation, here is what I have done. I pull out one frame in the center of the super. I pull out a frame in the center of the deep. I stack the two boxes, and put the deep frame into the top super so that it hangs partially down into the deep in the slot that is open in the center. The bees get a ladder up and start drawing in the super very well that way. Once they have a couple combs in the super drawn, then I remove that deep frame, cut off the comb hanging off the bottom of the bottom bar, and tie it into a super frame, put the deep back where it goes into the bottom and stack the super back on. Works for me, you might want to give it a try.