Under electrolysis, Evian did ok as the red is red oxide from the metal rods in it. Although something in it was a catalyst to bring about red oxide. Yes, tap water usually off gasses black specks like the two on the left. I've electrolysed "reclaimed water" which turned to black mud similar to smart water. Scary. Reverse Osmosis and Distilled are equal and have no reaction / no contaminants.