Keep the feed light Scott as has been said get pleanty barley in there. Best way to feed to keep it simple for now 50% barley 50% yb mix fill feeder up get them in and watch them eat soon as 2 birds go to drinker take food off them. Another thing feeding a lot of barley you can trap with seed or peanuts as the birds love it so they will be even more eager to trap. It's like having porridge every meal, when your mam shouts you in for tea your not to fussed, but when she's got the chocolate cake out and shouts your there in a flash
P.s your not flagging them are you? And do you have a flapper ?