Weigh your pig and convert it's weight to ounces. Multiply that number times .015 (or 1.5%). That is the number of ounces of pelleted Mazuri minipig chow to feed in a day. Divide that amount into two feedings a day. Provide fresh water at all times. Use the elder minipig chow as it is closer to 14% protein. The Mazuri company makes lab chows and dolphin vitamins. So their ingredient sources are clean of chemicals that are widely used by agricultural giants. Never feed any blended hog or mini pig chow made by an agricultural mill. They use the same sources for all their chows and it contains growth chemicals for slaughter.
Another way is to feed whole oats and timothy hay so you know it is clean of chemicals.