I was getting ready to put my aragonite substrate into my tanks, and I started to rinse it out because it says to rinse off the dust. When I added water to the bucket the water immediately turned dark brown. I rinsed it a couple of times and the more I rinsed it, the darker the water became. Should I add the aragonite to the tank, or should I continue to rinse it until the water runs clear???? Is the dark stuff good for the tank, and will it settle on the bottom if I add it???