In a very large pot, combine water, chicken broth, garlic, bouillon cubes, salt and pepper. Bring to a slow boil or simmer on medium-high heat, stirring to dissolve bouillon cubes. Carefully place meatballs in simmering broth one by one. You may need to put a few in at a time, until those ones float to the top (about 10-15 seconds), then add more. Do this until all meatballs are in the simmering broth. Temperature will drop, so adjust it to almost high until back up to a steady boil, then bring back down to medium. Meatballs take about 6-8 minutes to cook through.