I just noticed that several of my adenium have pink spots on the bottom sides of the leaves. And the leaves have pink/red edges. Is that normal or is it a disease that I should be concerned about?
Thanks,
Tin

Could possibly be a nutrients deficiency, although I can't recall the specific macro nutrient of the top of my head that causes reddening of the leaves. Try watering with trace elements once a week for a while and give them a good fertilise and see if there's any improvement. Could take a month or so depending on growing conditions.