Chicken feed can seem complicated.
All flock or multi fowl can be for chickens, ducks, turkeys mostly. Game bird feed is for pheasants and stuff like that, it has higher protein, usually around 24%. Starter or starter/grower is for chicks under 16 to 18 weeks but any adult chicken can eat it. For chickens over 16-18 weeks 16 or 17% protein it average. Sometimes you can give little higher for limited periods up to 20% during molting or extremely cold winter spells.
Layer feed has calcium in it which really isn't ideal for roosters long term so if you have roosters it's better to feed an all flock and give oyster shell calcium on the side along with grit. Chewy has Kalmbach brand which I find to be a pretty good brand - it's my favorite so far. But it can be pricy, sometimes you can get a sale or a deal if you order a few bags at a time (if you have cool, dry, mouse proof place to store them). I use Dumor and Purina too sometimes, whatever is avail at the feed store. There doesn't seem to be a huge difference really on the main brands available. I ferment my feed too which helps not only in how well they use the nutrients but they eat a little less when it's fermented so it's a better value that way.
