i guess I could use rain water but I don't know when the next big rain shower is going to hit. I'll check the weather. Right now its either distilled or tap and I heard tap is bad because of clorine. I'll call 'orchids limited' and see if the cultural info i got fro rivergate is right for the species. the rivergate people knew it was a tree growing species/ that they like to be tight in the pot and that its a wonderful orchid and has preformed well for them I do know thin rooted orchids like to be watered more then fat rooted ones, or so I have heard.