I wonder if anyone has done a side by side test of BB vers. sand. Start 2 identical tanks side by side, one with sand, one without, and see what happens over time. So far I have only seen speculation. Another experiment would be to wrap a small peice of shrimp in mesh and bury it 1/2" below the surface of the sand. In a week or so dig it up. If it's empty the sandbed is working, if the shrimp is still there (in any form) then it could be said detritus can collect in a sand bed
