So sorry I didn't see your question till now. I've been so busy getting ready to move.
I just use tap water.
Update on the phals...
I lost one
I noticed after several days that one had a leaf turning yellow. I moved it out of that window (East) to the Northern one. I just thought maybe it had been getting hit with direct light in the mornings too strong... Then, I picked it up a couple days later, and all the leaves just fell right off... All had yellowed, and fell off, the base was just deteriorated. So, the one that had zero roots did not come back.
The other one that had one or two aerial roots, is still green, still looks slightly wrinkly, but I am afraid to move the bark at all to see if anything new is happening under there!
The Rescue Phal has beautiful green tips on the roots I can see in the pot and a new root popping off the base AND a NEW LEAF!!!
Check it out!!! WOOT WOOT!!
It is hard to see but through the plastic I see the green tip of new growth!!! I hope ya can see the new baby leaf growing too!!! I am very happy!!