This is what works for me, my birds are confined...I do some fodder and ferment and garden scraps/weeds but keep these to smaller amounts, often reducing the daily scratch grains depending on the 'treat' and it's volume.
My Feeding Notes: I like to feed a flock raiser/starter/grower/finisher type feed with 20% protein crumble full time to all ages and genders, as non-layers(chicks, males and molting birds) do not need the extra calcium that is in layer feed and chicks and molters can use the extra protein. Makes life much simpler to store and distribute one type of chow that everyone can eat. I do grind up the crumbles (in the blender) for the chicks for the first week or so.
The higher protein crumble also offsets the 8% protein scratch grains and other kitchen/garden scraps I like to offer. I adjust the amounts of other feeds to get the protein levels desired with varying situations.
Calcium should be available at all times for the layers, I use oyster shell mixed with rinsed, dried, crushed chicken egg shells in a separate container.
Animal protein (a freshly trapped mouse, mealworms, a little cheese - beware the salt content, meat scraps) is provided once in while and during molting and/or if I see any feather eating.
Hi there - I'm in the same boat - one 2-year old chicken, 3 under one year chickens - all were laying fine until one went broody, and the rest of them stopped laying except for one. Could it have something to do with the broody chicken? (I've since broken her after about 2 months!). I've always fed the 16% dumor lpellets. All of a sudden, only one egg a day. I also give daily meal worms, or cackle berry treats, sometimes blueberries, kale, squash, etc. Maybe I'm giving too many treats? You're using the 20% Chick feed?