It will come down eventually, just going to take awhile for all the new media to grow bacteria on it. Keep doing what your doing with the wc regime. If you are having trouble getting them to eat try live night crawlers. It's hard for any ray to resist crawlers.
Have you tried using a 2nd test kit to test ammonia? Just curious, sometimes test kits can read positive and there is nothing there. Also if you use a live bacteria (prime) that contains inorganic ammonia, that will test positive for ammonia on an API liquid test kit.