Thank you to all who answered this question, both in public and in private.
I think I have the info I need now. :-)

"Al" wrote in message
...
A friend of mine just gave me a huge bunch of mother flasks of various
orchids and Polyrrhiza lindenii was among them. It is planted in very
skimpy media just a few mm deep and they are just protocorms with very
little root development. He says it is standard 1/2 strength Phytotech
P668
with charcoal. He says this species for him never develop roots and
normally die as protocorms. They are nice plump and deep green at the
moment. A few have roots less than 1/4 inch.

I would very much like to avoid the same fate with these and was wondering
if anybody could tell me if it is the media itself that is the problem or
just the amount of media. I will probably try to replate these onto a
deeper media bed, and probably use a clear/charcoal-less mixture soon but
other than that I am clueless....