Vanda with Black Spots?

[birdwomn]

I have several vandas that I got from a reputable vanda grower about 3 weeks ago. The three smaller ones have developed some black spots on the leaves.

Location: west central Florida, near the coast

Environment: outdoors, very dry conditions (for Florida), some cool snaps (down to 50s at night) but mostly quite warm

They did not have much to the roots when I got them and I have been watering them at least once a day, often twice.

I am not sure whether to be worried or not.

Note: I looked at several other posts about black spots on vandas and am unsure about these still.