Net Pots Question.... HELP!

Hey All--
Im about to set up my first bubbleponics buckets. I have my sprouts in one inch rockwool cubes and they are ready for the 4" net pots. Where do I put my rockwool cubes?? Do they go against the very bottom of the net pot? Or do I put some Hydroton in first and the the cubes. I feel as though if i but the cube at the very bottom of the net pot it will be sitting very deep in the net pot. Thanks!!

I am wondering this same thing

I usually put a small layer of hydroton rockthen the roclwool cube but it is not necessary, I like to have my seedling or clone as deep in the net pot as possible as most of that material will not be used for buds but structure.

regards,