I'm doing a 4x4 tray ebb and flow 600 w hps.
My question is I currently have the plants 4inch rockwool that's it. Is this okay? Once the plants get bigger I will use a trellis to support them. My main concern is the root system, will I need to put something underneath the rockwool, or can I keep as it is? I've researched it quite a bit and I've noticed tons of different answers. I'm trying to build a consensus. Thanks!