Need some help please, dnt wnt them to die... 🙏

Its already 12 days, put them to germinate in rockwool, and are in the medium coco/perlite, ph 6.2 water and i used terra trio 1/4 of rexomended dose + seaweed and some cal mag, why are they so stunt??? Please help me out, *sometime the light wasnt too stable on/off a few days but i fix the timer to 18/4 now since 10 days also i I didn't balance the ph water well before, but now am doing it..