you should keep the powerhead on, just make sure it is not blowing down in the sand. What kind of filter are you running, if it is a canister or any kind of mechanical filter it will probably clog fast with the water so cloudy. I am not familiar with the live sand, but I know the dry sand has to be rinsed very well and still clouded up my tank for about three days. I dont thing it should be clouding like that this long. I wonder how live it actually is. I really don't see how sand can stay live on a shelf sealed in a bag. Just leave it alone for a while, I think once the bacteria cultures take hold that holds it together some.