In crockpot, combine carrots, green pepper, and onion. Sprinkle tapioca over vegetables. Place frozen chicken pieces atop vegetables. For sauce, in a small bowl combine undrained pineapple, brown sugar, vinegar, soy sauce, bouillon, garlic powder, and ginger. Pour sauce over chicken pieces. Cover; cook on low-heat setting for 10-12 hours or on high-heat setting for 5-6 hours. Serve over rice.