Troubleshooting Phrag. besseae

[Dart21]

Beautiful!

I just picked up a besseae a few days ago. In the greenhouse it seemed they were having some mold issues on the foliage (these were potted in fine fir bark and sitting in a saucer of water). Intuitively, I picked up the one with no leaf mold that happened to have just arrived from Hawaii. It was potted in a very course bark/perlite/charcoal mix. On top of the mix there was some moss and it immediately started growing mold once I got it home.

I freaked out and repotted it very carefully as it was in bud and just about to bloom (don't worry it's in bloom now) in a finer mix with some added aggregate, set this in a glass saucer with rocks and water to provide humidity (bottom of pot is not submerged). This is proving to "control" the mold so far... but I can see small strands of hyphae creeping around, I need to rethink the mix, anyone have any recommendations? Have expanded ceramic available (similar to hydroton, I am considering as I know that no mold will make it in this), charcoal, medium grade orchiata bark, coarse perlite... Just want to get rid of this mold and allow this Phrag. to get as much water and nutrients as she wants...

Any other solutions welcome. I know besseae are very sensitive to water quality so spraying solutions could be out of the question... not sure. New to Phrags.