Best Tip ever - new question

Thanks for this simple and effective tip. I have done this on my city urn and country urn, even on a stovetop teakettle and its magic. I recently purchased a new Urn and the water has a metallic taste. I tried changing the water a few times but it still has this metallic taste. Any advice on how to eliminate the taste? There is no limescale in this urn as it is brand new.