Liquid for food purees?

[tattlebaby]

What liquid do you use for your purees? Is regular bottled water (poland spring) safe to use to boil your veggies with to then add this same water into the blender? Someone mentioned "Nursery Water"..whats the difference? I wish i could use Breastmilk, but as it is..I'm running low in that dept. so whatever I do pump i need to save for her bottles to give to her nanny. Any tips??