like and appreciate my tormek. use just for my own items. means sometimes sharpening a single knife. was thinking of getting an edge-pro or something similar to sharpen singles as would not have to fill tormek with water for a single item. any negative effects to the stone when filling with good quality 5/6 grain hardness city water? mineral buildup type thing? also wondered what is the effect on the stone if water is not used. thanks.