yes I would recomend washing the sand just like you would with crushed coral. you will have some debris in there. I would put the sand in a clean plastic trash can and turn the hose on it. I did this with my substrate and left iit in there till the water ran clear, even then when you put it in the tank you will still have quite a bit of time for all of it to selttle. I have heard good things about white castle sand.