It really won't kick back up at all unless you dig in it as in placing plants and the like. Some sand may compact but I've never had a problem but that could be because I have live plants and the roots will keep the sand loose. How the sand reacts (settles) when you stir it up also depends on the type sand you have. Cheaper sands like play sand are full of fines and dust and thus take longer to wash before placiing in the tank. Even after a thorough washing, there will still be some dust to settle and once you stir it up, you will once again see dust that takes a while to settle. Other products such as Tahitian Moon Sand, have almost no fines and settle immediately when originally put in the tank and when stirred up.