I've been growing sprouts year round to feed my chickens for a couple of years now.
The formula that I use for their feed is
1 part sunflower seed 1 part oats
1 part peas
5 parts barley
I double the recipe for my 24 chickens and add 1 cup of meal worms.
They also free range 1/2 the day if it's not raining.
I have 2 sets of wire racks with spray emitters at the top on timers to run 3 times a day. Each pan has holes poked in one end and each shelf has a 1x1 board at the front or back of the shelf that the trays rest on. This way when it waters, the water runs from one tray to the next and everything is watered.
I cover the shelves with aluminum screen and Avery wire to keep the mice out and drape a sheet of plastic over it in the winter to keep it warmer.
There's quite a few mats of sprouts in the last picture in their coop as they've been doing a lot of free ranging and were only "cherry picking" the sprouts. Nice thing is that the sprouts don't go bad, they just keep growing, when they're in mats like that so eventually they get eaten up