Agaveville

Been after this genus/species for a few years and finally acquired a seedling this spring! It is in pure mineral potting medium. They like to be watered weekly in this. Also did not like full sun, the leaves turned purple and it stopped growing. Now it is getting sun behind a shade cloth and the leaves have turned back to green with some new growth appearing. There isn't a lot of info about these anywhere so i'm not sure exactly what I will do for winter, maybe just light watered once a month to retain the leaves? Any info people out there have would be much appreciated!