Dwc EC too low ?

Too many nutrients for this particular plant, would be my guess. Baby plants need baby feeding, so I would be reducing the strength of the nutrients that this plant is receiving. Without knowing exactly what you are feeding this plant or which strain it is, nitrogen toxicity is what I am picking up from this picture. Hopefully others may be able to offer further suggestions. I am still going with excess nitrogen though. What may have worked previously with other plants, will not necessarily mean it will work for all plants, as in this case. Each and every plant has unique requirements, meaning feeding and water needs are also different and can be a bug bear if growing multiple strains using the one, shared feeding schedule. Hope this helps,........ Organoman.