The EPA set the maximum level as 500mg per liter. This means for every liter of water, not more than 500mg should be designed up of dissolved solids. There is some discussion on the subject, and it alters from state to point out. What is the encouraged level of TDS https://ph-water-tester22099.blogscribble.com/20084127/top-latest-five-filtering-shower-head-urban-news