I run two different Hydro systems, a RDWC 8-8 gallon system, and 4- 5gallon bucket DWC system, both I use Clay pebbles. Once plants are set and the roots finally grow in between and through the pebbles and reaches water, no need to move plants to disturbed roots tangled in pebbles until time to cut and harvest. Yes you have to break free the pebbles trapped in the roots, but its a small amount, most fall free, and remember , most of the root mass is below the basket and pebbles. Thats ime on those systems, I have not run a flood and drain, or have yet to use flood tables, peace