I used a compressed air blowgun, the venturi style, and some screens I use to clean grain for grading and measuring. It seemed with some practice I could get it to mostly blow the light, unfilled, and mildewed kernels out, and the ergot tended to gather at the bottom. But the black ones are easy enough to see and pick out. You can screen the rest out after malting because they won’t have a cotyledon and will fall through larger screens along with other ungerminated seeds.