In another thread MoodyMann posted a link to a website with various Japanese waterstones, and that site sells Chosera stones:
So, right off the bat I learned something, that the name of the new stones for my Edge Pro - Chosera - is actually a brand name from Naniwa and not a kind of stone. Learn something new every day. At least I think I got that right. Anyway, there is a note on the page about care of these stones that reads:
"IMPORTANT NOTE on storage and lubrication: Chosera sharpening stones are bound with magnesium and so have more cutting particles per unit of surface than resin-bound stones. But magnesium-bound stones are much more sensitive to prolonged exposure to water as other types of stones. So Chosera stones should NOT be left to soak in water for prolonged periods and must be stored dry. If this advice is not followed the stones can develop hairline cracks or the binding material can be leached out of the stone. It is more than enough to pour a little water on the surface or briefly dip the stones in water, they do not need to be soaked. If you are not sure that you can keep this always in mind, perhaps because you have a number of different kinds of sharpening stones, it may be better to opt for the more tolerant Super Stones."
Pretty much everything else I've read (and seen on YouTube videos) shows the stones being heavily wetted and/or soaked before use. More important, according to the above they need to be dry when stored. I am fine with cutting back on the amount of water I use, but for storage how dry is dry? Wiped off dry? Bone dry? Leave-out-on-the-counter-for-a-day-before-putting-away dry? I've only used the stones a couple of times so far. Just checked them and they look fine. Also, for the Edge Pro they are mounted on metal plates, so that might help prevent cracking.
Any advice would be GREATLY appreciated.