10-10-10 All Mineral 20 lb. Bag which covers 4,000 sq. ft.
For Fertilizing- Take half the highest setting, and subtract one or two.
Most of our fertilizer bags will tell you to spread 4-5 lbs. of material per 1,000 sq. ft., and this formula will work for almost any broadcast spreader- Half of highest setting minus 1 or 2
Example: If the highest setting on your spreader is 20, then set your spreader at 8 or 9to spread fertilizer.