Using red lava rock for outdoor orchids?

[SaraJean]

I recently acquired a gorgeous Den. Spectabile from an orchid show in my area it looks as though is was recently repotted but I really don't like the media that it is in. The current media is way too water retentive for my taste since most for my guys are grown out in the elements. I am seriously concerned about root rot and would like to switch out the media to something very fast draining. Has anyone, especially those in hot and humid climates, had much experience growing their dens in red lava rock? Some people say it is too water retentive, others say it dries within a day. I have also seen an article stating that it changes the ph of the water (can't recall off hand if it made it too acidic or too alkaline). I also have some leca that I could use or combine the two together.

I am also wondering if there would be any difference in switching pot types. It is in a net pot right now, could switching to clay do more harm than good? I like clay simply for aesthetic reasons and don't mind experimenting, but this orchid is too pretty to kill over something petty

Thanks!