I did not have any mold problems with barely seed fodder last year. This year I started off with wheat seeds and lost my first few bins to mold. Nobody wants to grow moldy fodder for the compost bin.
@WannaBeHillBilly has already outlined his method of preventing mold, which is pretty much in line with what I also do with my fodder. I know temp and humidity play an important role in the growth of mold. When I reduced the amount of wheat seed in my bins, thereby allowing the seeds to dry out a bit more between watering, the mold problems have gone away. That is kind of like a trial and error method, but it seems to be working for me.
Just curious, what seeds are you using for your fodder?
I have never tried growing fodder in dirt, well, actually, that would just be growing the wheat, barley, oats, etc... and then cutting off the green grass part to feed to the chickens. I don't have that option here in northern Minnesota, at least not outside. If you live somewhere where you can grow grass all year long, then you might consider planting your seeds under a feeding/grazing frame made up of 2x4's and wire on top. The grass portion of the grains grows up and over the wire, the chickens can eat the greens, and the roots remain firmly planted in the ground to continue growing.
As to feeding fodder to the chickens, they eat not only the top grass portion, but also the root mat with the sprouts and remaining seed that did not germinate. Everything gets eaten. It is fun for me to watch some chickens dive into the green grass, while others immediately start tearing apart the root mat to get at the sprouts.