sick seedling

OK here I am again with the same problem as last grow although THIS TIME I'M USING CANNA COCO. LAST TIME WAS SOIL. OK folks il start with the setup. 4x4 grow tent 15litre fabric pots 4 Auto stardawg Ph 5.8 Temps on 27 off 21 Humidity about 46 lights on about 60 lights off Extractor fan and small...