Public enemy has a point. If your just using bagseeds and you have a lot of them i say just grow a lot of them and pick the most healthy ones to keep. Say plant 3 pseeds for every plant you intend to keep and 2x the amount of plants you intend to keep as the amount of females you want so if you want 3 females plant 18 seeds. That way you can observe problems over a larger group of plants. If one plant isn't devoloping as well pull it.
With that said seems like you said you changed a lot of stuff. How can you possibly decide what works and what doesn't with so many variables. Just change one thing and watch for a few days to watch what happens or take one plant and change something from it but leave the other plants for comparisons don't change anything else.
Anyways have they been potted in those big pots the whole time? That's probably your problem. Plant in smaller containers for the first 2 weeks and than transplant into the of soil. Try the FF LW or jiffy pellets or jiffy mix something so they just get water and a light medium to start growing healthy roots. Than when you transplant the healthy roots will expand into the OF that is enriched with organic ferts.
From now on water the entire medium until it is evenly moist than let it dry out a little between waterings. Once your roots grow into the pot better and your plant will get bigger and your problems should go away.