In the very first grows I started with the nozzles on top, the roots then massed to the top completely covering the nozzles. I found that by starting the grow with nozzles at the bottom seems to encourage that nice tap root. When the tap root gets 6-8 inches long with the beginning side roots, I then switch to a chamber cover with the nozzles in the top
These roots are the fish bone structure……I aim for, the side shoots should start filling out now.