weird. I've been using them and used other fertilizers and biobizz biogrow is quite nice.
the FF might be better, but they aren't available around here.
however, my plants rarely suffer from any N def. as I usually catch it really early.
I'm not claiming bio-grow to be the best fert around, I really don't, but I do claim it is enough for soil grows N-wise.
If I had access to the stuff sold in the US I wouldn't even think of buying biogrow. I'd just get some high N bat guano and very low emount of bloodmeal. Used the bat guano when it was available, the powdered stuff, and it was like a miracle. That shit is pretty cheap too. you can get a 1.5lb bag for 16 bucks and thats a LOT of fertilizer.
If only add-ups needed I would get some liquid guano or go cheap and use diluted urine. or if an air pump and air stone available make tea out of the dry guano.
But I don't have access to all thoes things. The only "good" organic fertilizers around here are biobizz.
I have my hydro plants to compare as for health wise, and my organic ones are not suffering from any N def. (They are however much slower and much weaker)