Nute Burn?

Seems like the start of a Nitrogen (N) burn! kinda hard to see exactly which toxicity it is by this picture but your diary gave the answer! Leaves developing a dark green coloration while still in vigor were the clues. Try lowering your biobizz "Fish-Mix" to about 1.5-2ml/l and the "Bio-Grow" to about the same amount to lower the Nitrogen uptake. Also try lowering the Cal/Mag to about 0.5ml/l to avoid toxicity, it is a micro-nutrient and the plant does not need that much without showing a deficiency! Hope this helps! Good luck and happy growing :)