+1 on that my freind ... But the sand is going to get brown and maby some other clors dont mess around wit it let it be and when you cycle is donr the snails will take care of dont stir the sand cuz its just going to move all the bacteria all over the tank and your nit will go up the roof .. good luck on your biuld and keep up informedThere really isnt a way to tell. However over time a couple of weeks or so the sand will be cultured with tons of bacteria thats benefical to your system. If using cured live rock there will invaribly be many spores and several critters that will migrate of the live rock and move into the sand bed where they will call it home. The more diversity of such life, the healthier your sand bed will be.