Miltionopsis Seedlings under T5's

[orchidsarefun]

I am planning to experiment with the above in my basement. I have 2 Hydrofarm 4ft stands with High Output T5's. I have used them for veggie seedlings, but never orchids.
I have a concern about humidity levels ( maybe water trays, or in an aquarium? ), but the cooler basement should be perfect for the milts. They will be close to an underground basement window that gives a fair amount of natural light, and cooler temps.
Any suggestions ? How close to T5's as they grow ? How long do I leave the the lights on for ?
Thanks for any input.