Vandas require high & relatively constant humidity in the root zone. That might not be real practical with clay pot & bark.
My personal choice is Vanda basket with spaghnum & bark (4:1 ratio). With that combination, I water twice a week in winter & three times a week in summer.
If you are are prepared to water daily, you can grow Vandas in an empty basket (or simply tied to a wire hanger).
For more details, you can go to:
Fair Orchids