Repotting a large phal with lots of aerial roots...but nothing in the pot

[vyltan]

The picture says it all: large phal with 8 leaves, lots of aerial roots but everything rotten in the rotten medium. I know from experience you don't try to put aerial roots in the medium (new zealand sphag for me): the velum is quite different and won't adapt. But new roots grow only between leaves...will new roots ever sprout from the base of the plant? How can I get a root system in the pot?