Boron deficiency?

Hello all, I'm at my wits end.

Please refer to the attached photos.

Media: sunshine 4 with 30% added perlite
Lights: gavita 1700e dimmed to 500-800 ppfd
Sealed room
Solo cups > 2 gallon pots > 5 gallon pots
Just hit 5 weeks veg from transplanting rooted clones.
79.5F - 83F
68-74% RH
CO2 900-950 ppm
Tap water 140-150 ppm
Feeding currently at 5.9 PH, 950-1100 ppm with grotek nutrients including, pro silicate, vitamax, calmax (periodically).

I'm thinking this could be a boron defficiency? A flaw of mine is I tend to really let the pots dry out, I have read this could be a contributing factor to boron def.

I had good runoff ph but high ppm (1700) about a week ago so I gave a good flush, once dry fed with 1/2 strength nutes and some power Si, starting to look a little better but want to get to the bottom of this.

Any thoughts would be much appreciated.

I don’t know anything about Grotek nutes but plants use so little boron that I can’t imagine that’s your problem.

looks like boron it is staying away from veins, could be cal/mag showing weird though boron deficiencies are quite rare

oh i didn't see you were using sunshine mix #4, its got a ppi of over 1400 which is awful for cannabis plants. i used it my first few grows and ran into issues people had never seen before. im willing to bet its the sunshine mix thats making weird stuff happen. Promix BX is a great along with fox farms (foxfarm is $$$ but worth it) i havent had any weird issues since!

LJ00 said:

oh i didn't see you were using sunshine mix #4, its got a ppi of over 1400 which is awful for cannabis plants. i used it my first few grows and ran into issues people had never seen before. im willing to bet its the sunshine mix thats making weird stuff happen. Promix BX is a great along with fox farms (foxfarm is $$$ but worth it) i havent had any weird issues since!

Click to expand...

I suspected the SS#4 as well but I have one young future mother in the room in coco that is showing the same symptoms.