Apple-A-Day™ ElectrolyteFinish Line Apple A Day is a daily, cost effective electrolyte that does not contain sugars, fillers, or artificial colors. This proven electrolyte promotes healthy water consumption and replenishes electrolytes and minerals lost in daily activities such as sweating, urination, and defecation. Apple A Day has the necessary electrolytes and minerals to keep your horse properly hydrated, improve appetite, and support healthy nerve and muscle function.