questions about moving phrag to s/h

[neophyte]

I just have a few concerns about moving a recently acquired phrag to s/h. It is starting several new growths, so I'm not too worried about the roots. Mainly, I'm wondering 1) whether the top layer might get too dry, 2) whether the evaporation can chill the roots, and 3) whether s/h can amplify issues with high-ppm tap water.