yes, I have 3" sand bed, and its fine sand, but its about 1.5 years old, so its really packed down. Only on the highest power settings it blows around. I run one gyre during the day at 30% (for my clams sake), and run both at night at 40%. I got my first gyre back in Aug or Sept, I still havent cleaned it yet and still runs fine.
I think it will mess with your sand if you don't have it set very low (<30%) I have 1/2inch of sand in my tank and it gets piled around. I just live with it.
