You can use filtered tap water, but not tap water. Using steamed distilled is another option.

Sure. Let it stand, uncovered, for several hours. That will allow any excess chorline to escape. USA tap water is fairly safe. If you would drink it then it will work for enemas.
That said, not all US water is the same. Some rural areas have a lot of dissolved minerals. But for simple cleasning enemas tap water is fine.