Maybe some of his records aren't all that priceless!
Like Dan and Stltrains, we rinse with water that's much purer than Aquafina. That water meter would probably measure 0 ppm.
I spilled bit on the counter yesterday. In a few minutes it dissolved a residue I didn't even know was there, a residue normal household cleaning products don't remove. The formica was left distinctly whiter than the surrounding area.
As Viridian knows (having wasted so many years chatting with us audiophiles!) lab grade water is a powerful solvent that's actually unsafe to drink. Different applications, different products.