We put in new tile floor in our kitchen, livingroom and bathroom. It looks great. We had a small water leak in the wall in the bathroom. The floor under the livingroom got wet underneath. Now we have this bloom of "salt" coming up through the grout. We have tried scrubbing it, putting tilex on, we have even put muriatic acid on it. It goes away for a few hours and then it is back. Anyone have any suggestions or know how to get rid of this?