I have been working with HepG2 cells for some time with no problem. The past couple months when I've been plating into 96 well plate for experiments I am noticing the cells are not healthy or growing. The same cell line in the T-75 flask are growing well. Pictured are the cells in the T-75 compared to the 96 wells. From the same cell line, plated the same day. What could be going wrong?