I grow all my paphs in a media/mix called "GREENMIX"...Its a special produced rockwool based media with a bit of limestone in...It is produced here in Denmark only but is sold worlwide, tough shipping costs may be high as it comes in 5 and 10 kg bags only...I have been using it for about 25 years of the 40 years I have been growing orchids, and it is a excellent media, especially for terestric and botanical types who needs a bit more humid compost in the pots...I have all my paphs and a Phr. kovachii in it and the kovachii just loves it as it needs clean, clear water almost constantly so this mix is great...