Stunted growth is due to too many nutrients... as we are 3 weeks after you started using your nootz ( problems starts 3 weeks after in soil , always ! ) .
The plant is stunted due to an hypertonic conditions in the soil ( too much salt , unused nutrients always build up into salt ). Technically and normally nootz burns shall start to show next week.
It was still a smart move to backup the light as they were miniaturized.
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