DRAINAGE is a definite need. home depot carries the orchid bark mix along with the sphag moss and otheres. very cheap for the most part. clear plastic is good bc you can check outer roots... there are alot of repotting tutorials for phals... def worth a watch...potting mix is what ever is comfortable for you but mostly whats best for the chid... and how it responds... im switching to leca and s/h bc i heard it works wonders. some i plan to mount on live trees. if the roots look rotted and are squishy flat hollow feeling...repot cut all dead rotted roots away.. sterile cutting tool for that!.. you will have more comments and input soon

good luck!!