I guess this is what you get when you don't acclimate to different light gradually enough.
Most info I read said to give this Epi. Miracle Valley "nodeshika" similar light to Cattleya (I know, not very precise), and it's always been on the bottom shelf under a 315w cmh. The new growth is a more appropriate color.
E.Miraclevalley.jpg - Google Drive
I think I made a good decision to repot, because the mix it came in was fine, compact, and didn't get much air. All are getting watered daily at 15-20 ppm N.
If that isn't the cause of that "purpling" I'd like to hear an opinion.
Just for fun, here are some root pics of my C. aurantiaca, from 8/30 and 9/4, which was purchased the same day and resides on the top shelf.
C.aurantiaca8/30.jpg - Google Drive
C.aurantiaca9/4/20.jpg - Google Drive