i would try to use rain water if you can
the water that runs down your gutter into the drainage is perfectly good. It just stops all the stuff they put in drinking water gettin on your plants. i've seen it leae white marks on leaves that doesnt come off if you live in a hard water area like me.
i also dont water the leaves, it can sometimes get water into the crown which isnt good. i usually dunk my orchid in a tub of water, so the medium surface wont get wet either.
part from that your doing a great job, its very important to get all the info early on like you have