I wanted to try replacing the grower crumbles I've been feeding with the co-op's layer pellets. I had about half a feeder full of crumbles left but thought mixing new with old might result in billing out and a big mess. So, since I have two feeders, I emptied one into the other and then filled it with the pellets and then just left it for the birds to choose. They're eating both. I'm pretty sure when the crumbles run out, nobody will be upset. And boy, will I be happier to pay $4 less per bag!