ace potatoes, carrots, and onion in 6-qt. slow cooker.
In medium mixing bowl, combine ground beef, egg, 2 tsp. salt, and 1/2 tsp. pepper. Shape mixture into 1-in. balls. In large skillet, brown meatballs on all sides, adding a small amount of oil if necessary to prevent sticking. Drain if needed.
Place meatballs on top of vegetables in slow cooker.
In small mixing bowl, combine water, tomato sauce, brown sugar, vinegar, tapioca, basil, 1 tsp. salt, and 1/2 tsp. pepper. Pour over meatballs.
Cover and cook on HIGH for 4-5 hours, or until vegetables are tender (OR cook on LOW for about 8 hours, or until vegetables are tender).