first timer ,my seedlings won't grow. '3'x3'x6' grow tent,1500 watt cob led grow light, 5 gal. smart pots,FFOF potting soil with an organic super soil concentrate (I used as directed (bottom third of the 5 gal pot mixed with FFOP), autoflowering seeds. I started the seeds in the 5 gal pots (to avoid transplant shock), 20/4 light schedule. Watered as needed(dry to first knuckle),they grew about an inch or so then stopped .They had their first set of jagged leaves. I pulled them both after 2 weeks of no growth . the roots were black. Temperature between 70 and 80 f, humidity 50%. "am I over watering?