How long for sand to become "live" in a refugium?

[Gatorfreak]

I just setup a refugium for my 90 gal with extra aragonite sand that I plan to use to establish a 10 gal for a mantis. How long should I expect it to take for the sand to become "live"? FYI... I already have LR that has been in my sump for a year that will also be used in the 10 gal.

 

[DragonForce]

Shouldnt take about 2 weeks to have the bacteria growing on it. You might want to throw a peice of LR from the display in there to speed things along even faster.