our concept of "live sand" and bagged sand vendor's concept of "live sand" are two different things. The stuff we want living in our sand will not survive in the bag.
Imo get 0 bags of live sand and all dry aragonite (or better). Toss some live rock on it and eventually you have live sand. You can also ask a local reefer with a good clean tank to scoop out a cup of sand from their sand bed to help seed yours.