We Had A Water Filter System With Potassium Permanganate In

We had a water filter system with potassium permanganate in part of the filter system. We found it in our salt filter one day. We had the filters analysis and the results are manganese for one liter is 4.76 ppm 0.02 potassium 113 ppm 2.00 . Do not know the results of our blood test yet. But is there suppose to be potassium in our drinking water and is there manganese is drinking water? The bottle of this stuff warns not to ingest it.
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