you have to get some potting soil it can grow in that type of plant food they need food to even younger plants need support give that a try and see what happens see if it takes on life after that
Is your light powerful enough? 400-600 watts is ideal. As long as its getting 18+ hours it should be growing. Be sure not to overwater it too that can stunt growth.
Your light might not give off the rays that the plant needs. At a week mine were nearly five inches if not more. I used potting soil and a 400 watt bulb in a well ventilated room with foil on the walls in order to conduct light.
I do have it in potting soil and limestone