I have white leghorns and their diet is the same as the marans, layers for the most part, they get a treat everynight of a small ration of mixed corn with dred herbs in (oregao, thyme, basil, dried garlic powder) this is about a large handfull between 5 chooks and I use ACV (2%) with garlic in the water every other fill.
I do find their poops can be on more occasions than the marans be a little wet.