Don't over think, just conform.....lol I have always used aquarium water to mist with. Not only is it vitamin and mineral rich, but since I dose my tanks with fertilizers, it's even more beneficial for the plants. Of course, I also know the precise amounts of ferts in my water, so I can keep it at acceptable levels for all myplants and animals . I don't recommend doing it that way to anyone. I only do it that way because I have been growing plants indoors a long time .