if you look at the tank on the right of my signature you will see that one also has black so this is my second tank with black aragonite , i wasnt aware of any negatives regarding it , please inform me ? this is year 3 of using it and i have had zero issues with it , it looks super sexy specially under LED , it doesn't show dirt like white sand does , its coarse and heavy enough not to blow around and my tube nennies,sand sifters and star fish dont have any issues with it either