I have been searching around for some black sand that buffers the water and looks good at the same time. Most of the sand that i have found is black with white specks in it. Not really what i was looking for. however i came across this black sand called "Bio-Activ Live Aragonite Black Reef Beach Sand". It is just what i wanted as far as the grain size and look. I ordered 5, 20 pound bags of it at 29 dollars a bag. "GULP"!! Last night i was talking with a friend that said he heard that i would kill my fish if i put it in my tank because it is for saltwater. Is this true?? I am gonna rinse it very good. I figured that would be ok. Am i wrong? Thanks. Lee