Thanks for that
@budelee there's always some one around that knows there gear
Honestly it looked way further then 28in but photos do play tricks! Lol
As for the purple usually it's nothing to worry about, some strains are naturally purple (dark devil) for example, then you've got your night time temps, if they are low it will cause the plant to turn purple again nothing to worry about here, I like the purple on my plants.
Another thing is nute deficiency, someone correct me but I'm pretty sure low magnesium will turn it purple,
As for those dots im not to sure, they look small and not a great deal of them, I'd keep a close eye on it, maybe someone else actually knows what those dots are?