Help me pinpoint the nutrient

kind of a strange thing going on, and i have some theories just need input..first off:
perpetual grow,12 girls, vegged 6 weeks, in 5th week of flower, 3ltr air pots, clay pebbles only, in 2x4 trays, top drip recirculating, ppms 1500, temps 75, res 67, DM gold line, Bloombastic, 1500watts.

so i have this table with 12 girls, 6 different strains, two strains are yellowing excessively, had the ppms at 1250, so i raised them to 1500. and set the timer to water every 30min i also use a decent water filter, but either way my ppms are 30-80 from the tap. these two strains are the biggest of all, and really blew up in size throughout veg and early flower.

monkey wrench: The strains are strawberry cough and sweet tooth, but one of the sweet tooth plants is perfectly fine, although it is about 1/2 a foot smaller so its not a strain thing i think.

My theory:
These two strains due to their size require more nutrients, specifically nitrogen. they plenty of phosphorus due to the "Bloombastic", and i even throw in some "magic cal", cause i one point i thought it was a cal mag def.

i bought some "magic green" yesterday, its suppose to fix this, but i could care less about color, i just wanna mag sure bud growth isn't stunted.

so what do u fellas think?

Iron, or zinc with new growth. Nitrogen is from the bottom up.
I can't really see the pics get some more pics looks like you have some brown spots on the leaves to the right.

Can you get a close up of some of the leaves?

Looks like N to me. Usually with N it will be a solid uniform yellowing like that on the bottom leaves and progressing upwards effecting larger older fan leaves first.

thats what i have in mind, i just wanna make sure thats all it is. magic green will take care of the N.

You can find that some strains are more nutrient ppm intolerant than others and that can lead to root stress and then on to nutrient lockout. When it gets to that stage it doesnt really matter how high the ppms are, the roots just refuse to uptake nutrients and then the plant turns to pulling the nutes from the leaves and stems as its primary source. If you just had the one strain there you could back the ppms off to allow for the roots to recover, but in your case, the other strain which is doing ok would then suffer. So best just stick to what is working for your best strains and the others will just have to tough it
out.

If that is the case then next grow just one strain per hydro system would be the better option

thats nitrogen for sure. its lime green, and the oldest growth is affected first, so yellowing starts at the base and crawls up the plant.

from dirtsnowball; heres some reference pics:
no hate meant, nitrogen deficiency early stage -note the overall lime green color with lower leaves yellowing



healthy: -note its a bit darker than a punk rockers lime green Mohawk



nitrogen toxicity: -note its a bit darker than any green crayola crayon i've ever used

Click to expand...

time to feed. good luck!

Jonus said:

You can find that some strains are more nutrient ppm intolerant than others and that can lead to root stress and then on to nutrient lockout. When it gets to that stage it doesnt really matter how high the ppms are, the roots just refuse to uptake nutrients and then the plant turns to pulling the nutes from the leaves and stems as its primary source. If you just had the one strain there you could back the ppms off to allow for the roots to recover, but in your case, the other strain which is doing ok would then suffer. So best just stick to what is working for your best strains and the others will just have to tough it
out.


If that is the case then next grow just one strain per hydro system would be the better option

Click to expand...

i hear what your saying jonus, and i came to that conclusion as well, but then i noticed the other sweet tooth plant wasnt effected, so dunno...