I can't use mash feed in some of my pens. In the summer with the humidity it will not fall and we are having to fight it to get it down to the feeder. I can mix it with pellets to make it work better. My litter bucket feeders are ok for mash feed. Personally I prefer Tuckers feed. It is pork based and much better for chickens than a vegetarian feed. Chickens are not vegetarians... mine don't get to free range to get bugs so it just works much better for me. I also get the 22% even better for the chickens.