Going to try something with these 6 seeds. Possibly a SOG/SCROG. 2 rows of 3 seeds in a 50cm2 proscrog frame. Depending if they do a quick stretch, and aren't suited for it, I'll abort it and adapt them to a better method but remaining in 1 20L pot. 60/40 in pebbles favour. Nearest thing to DWC. Will be tricky with ph. My water is high. Also, I crushed 6 seeds little stem by not putting them into a piece of rock wool or cube to protect there frail stems. And the high clay content broke ALL that weren't added in with their cube. As I just started tearing the ends off the cardboard, as I should have done. I kilt of 6 seeds in 1 start. Massive school boy error.
If I Have to cull the 2 in the middle or take 2-3 out if the phenos get leggy. I'll adapt them to get good weed either way. Hoping the sog/scrog will work. Let's see. This substrate is a bit demanding and will need daily tending.