tort vs milli should be a noticeable difference with both the coralite structure and the polyp extension. Milli are “hairy” acros and when happy they have long polyp extension.
Acros grow differently depending on the species, a stag will grown in a much different pattern then say a tabling Acro.
As far as lightening and placement that depends on the species and where it was collected. Deep water varieties like lokani, carloiniana, granulosa etc typically do better towards the bottom of your tank but bottom vs top is a relative term that depends on the light available for them.