Hey... just curious about how your Vandas are doing! I potted mine in LECA pellets in clay pots, and they are LOVING them. My plants came as free gifts, so they're not blooming size yet, but I think I might just be able to bloom them if I keep up what I'm currently doing. I water every other day, and the LECA pellets seem to give just the right amount of moisture to the roots while being able to dry out again quickly. They get morning sun in an Eastern window and afternoon sun in a Western window (yes, I move them back and forth every day) and they are growing happily.
Did you say you had ordered lava rock? How is that going? :-)