quick run down for you mate.
View attachment 799709 see how everything looks dark, thats too much nitrogen. that can slow the growth. theres a couple of things can cause that colour but if you look closely at the tip of the big leave in the middle and the one on the left, the very tips of them are clawed downward. id imagine they dont feel right iether. kinda paper like, thin or dry maybe. if the tips claw down like that its too much N every time.
if the new growth, and only the new growth, nowhere else, starts turning yellow/ light green from the stem towards the tip, like that.
View attachment 799710 then you need to add some calmag. make sure its a brand with no added Nitrogen. i use one with extra nitrogen so again someone else will have to help you there.
itll get busy here again in an hour or so though so just chill for a bit and all will be revealed my friend. the yanks are mostly sleeping and we in the uk are mostly lazy lol