I just started growing clones from a white widow plant in a ebb and flow hydroponic system . This is the first time growing hydroponic pot and my plant are turning yellow in color.????? I have added the nutrients to the water according the product calculator chart and I check the Ph level daily ( 6.0 to 6.5 range). What am I doing wrong? What nutrients

are the plants lacking?
Any advice would be greatly appreciated...thank you