First, you could always go to the store and buy distilled water. To answer your question, yes, but with a caveat. Fortunately, macros are a bit more forgiving in this way.
If your water has a fair amount of iron, it could interact with phosphate and could reduce the amount of phosphate you are actually dosing. You also may run into solubility issues if you try to make it too concentrated.
For micros, pH is more important, so it would be advisable to do distilled, lower pH with an acid like ascorbic or acetic acid (vinegar), then add micros to the solution.