Alfalfa is not horrible for horses... Although grass hay may be more nutritionally balanced, some Alfalfa in the diet is fine for horses. How much does each flake weigh? Flakes can weigh anywhere from 2-10 pounds, so I have no idea whether you are feeding 1 pounds or 5 pounds. When my horse is only being fed hay in winter (no pasture) I feed 5 pounds of Alfalfa and 15 pounds of grass hay.
“Good things come to those who wait… greater things come to those who get off their ass and do anything to make it happen.” - Unknown