sand floating around on water surface

Hey everyone. I was setting up a marine tank tonight, and ran across a problem. The guy at the pet shop recommended that I get "live sand" to kick off bacteria growth. He also suggested I supplement this with some regular marine sand. After adding water, i have a pretty thick layer of sand floating around the surface. Will this sand settle on its own?
thanks

Jer

not yet, the only thing i've done so far is add sand, live sand, and salt. I don't want to run the powerhead or filter until the sand has settled, and it has settled a lot overnight. thanks