Thanks for the comments guys. Reason I ask has to do my going back and forth between big-city tap water and small-town mountain spring water, and noticing better results with the latter. But it is a subtle thing bordering on superstition, so I appreciate hearing other takes on this here. A few quotes follow:

Quote Originally Posted by JOB15 View Post
Evian is the good stuff imo.
Agreed. Evian is similar to the mountain water I've been using with good results.

Quote Originally Posted by hein31 View Post
Through watering and drying cycles you enrich the non-evaporating contents of the water. Since high grid stones don't have a high porosity, this excludes any problems. Lower grid stones have a higher capacity for water, but you have to go through thousands of watering and drying cycles to assume any effect at all. The viscosity of the fluid however drastically changes the performance, but if you stay with water only (no glycerine, soap, oil or simple green) then viscosity is not changing at all.

So: no influence at all.
Wow, your very first post on SRP. Very informative. Keep posting!

Quote Originally Posted by Glock27 View Post
I would suggest using distilled water. As a personal preference, and out of ignorance, I will not submerge my Norton Stones in anywater other that distilled. My anecdotal experience with local tap water disturbed me and made me avoid any water that contained minerals.
Yes, I agree that distilled water should be the neutral default. And it's not all that expensive compared to, say, proprietary honing oil solutions.

Quote Originally Posted by thebigspendur View Post
People have been honing with whatever water they have for centuries with no ill effects on the hones or the razors

That's good enough for me. I use tap water.
Point taken, but there is a subtle difference between the use of a stone from anywhere on the planet with treated tap water and the centuries-long symbiosis of using a local stone in combination with a local water supply.