I hear that rainwater contains nitrogen and minerals that tapwater seems to be lacking, so if we live in the country and only have water from the well for house and garden needs, does that mean that our water has the same nutriens as rain water? Or would it be stripped of some (what?) elements as it filters through soil and by the time it gets to the well. The water level is about 20 feet down into the well, but the well itself is deeper.