Several factors determine how much they will eat. Important things to keep in mind are:
- Size of bird
- Age of bird
- If they're laying or not
- What you're feeding
- If they're have forage or not
So, an old bantam hen that's not laying, free ranging, and eating Layer will eat less than a Jersey Giant that is producing a lot of eggs, not foraging, and being fed Scratch. And some hens will just eat more than others.
.25 pounds per production type hen per day (with a 15-16% protein Layer food) is considered average, so, I would give them like one serving more than that to start with. So for six hens, 1.75 pounds. If they leave some, then about 1.50 is provably good. If they eat it all, you could even add some more if you wanted. Chickens will leave food if they're not hungry, so don't worry about them overeating.
This isn't an exact science, since there's so many factors involved. Just go with your gut.
Oh, and if you have chicks, it's best to make sure their feeder is always full, because they're bound to loose about half of it.
Hope this helps!
~~Ms.B
