I personally prefer coarse river sand (not fine beach sand which can impact a chick's crop) for my coops/runs as coarse sand desiccates droppings, does not retain moisture, does not decay or degrade inside the coop, has superior drainage (if water spills), is inexpensive, is Eco-friendly, can be removed from the coop, washed, dried and reused, is a natural grit with no risk of crop impaction as with straw and hay, is easy to clean-up, keeps feet clean and nails manicured, keeps feet and eggs cleaner (particularly in rainy conditions), any food dropped on it gets eaten not lost in the litter, is a dust-bath mecca, does not require decomposition in a compost pile, is a great soil amendment to compost, keeps coops cooler in the summer (provided the coop does not have a glass roof and direct sunlight all day), is an outstanding choice in the winter because it evaporates moisture more rapidly than other litter and stays drier, reducing the risk of frostbite in the winter, retains warmth better than any other bedding, and given its high thermal mass, it will keep coop temperatures more stable than other litter choices such as pine shavings and straw, and it looks cleaner than other litter options because it is cleaner.
