Definitely nitro bro! If you're organic like me, at 3.5 wks in I'd probably give em a shot of fish hydrolysate or Pure Blend Pro Veg to green em up a bit!

thanks!!!!1

Calcium nitrate will cover both bases and green um up for sure. You're probably going to lose a few of the large fans regardless.

I agree a shot of veg nutes and should be ok. Week 3 im stripping fans off anyways. Thin em out.

I am about to feed a hit of grow nuts. But I am perplexed by these leaf symptoms.
Only one of the strains is doing it but it still has me confused.... grrrrrrrr
Notice in the pics the brown spots on the new growth of some of the leafs..
Also notice that all the tips of the leaves and curled upward.

This is making me think they are mabey locking out.. Too much NPK????

I have been feeding at 1.0 EC.

I has been using the same nutrient mix. Veg + bloom for over a year and have not had any problems.
I am running new strains but all new strains are tuning really!!!! yellow.
The other new thing is the I am using reused soil... ( not going to do that again) ... And I did not amend it with green sand ( of which I am told means i a depleted of cal/mag.
My last watering I did was with only cal/mag.

U guys think I should hit it with a heavy grow NPK..... I feel like the veg+bloom that I have been feed should have covered this... BUt mabey they just need more......

Thanks again.... Sorry if it sounds like I am spinning in circle.... well then again ... I am .....

You need to up the nutes... 1.0EC in my opinion is way to low for week 3. They should be around 1.6-2.0EC.

The yellowing with burnt leaf tips is a sign of calcium deficiency. If you were over feeding the leafs would be dark green with burnt tips as well as the serrated edges burnt. Also the purple stems is lack of phosphorus.

I think you should give the plant a good flush with .5EC mix. The right after give them a higher nute mix around 1.6-2.0EC.