Young leaves yellowing, loss of smell. Week 5 flower - Help!

[sneakythumb]

I am starting to see this problem develop. the new leaves in on buds are turning yellow, seems like growth is stunted. Loss of crystals and smell. Starting to smell like grass. Only 2 strains are exhibiting this. but a couple more are showing minor changes. Looking on the net it looks mostly like boron. but does anyone have any ideas or info? thank you.

 

[WizHigh]

It maybe Zinc or sulfur def. But I think it a more zinc deficiency since you said the growth stunted. Did leaves seem to get a bit smaller?

 

[sneakythumb]

Leaves look like they are around normal size. Just the one thing that pointed to boron for me was the bud abortion. Like buds stopped growing and smell is lost along with no more crystal production. I gave a couple good flushes. One with flushing agent to assure removal or any buildup as when I tested my runoff it was higher.

food ppm: 1200 in week 5
under 7 -1k hps
nightime temp: 70-72
daytime temp: 82-84
humidity 50s
do run co2 but at low level 600-800 ppm

I did have two days where I must have hit my timer and lights came on 1.5 hrs early. But it was starting to show symptoms before that.

 

[sneakythumb]

Oh yeah Im using coco. I have used this brand NF-Nutrifield once before and it drained way too fast and I got this problem before and couldnt figure it out. But it started the last couple week. Im starting to think its this soil.

The runoff was 1900ppm. When I give it food of 1200ppm. Was using tap water for first half of grow but have switched to RO. when I was using tap water I had it in a res with airstones to aid in the removal of that chlorine smell and aerate it some.

 

[WizHigh]

I wouldnt use tap water. Coco and RO water will do the same to your plant. The problem you were having was probably a calcium/magnesium deficiency. They both rip thos nutes from the plants roots. Also you have to flush once a month or twice depending on how heavy your feeding. The ppm was high probably from a salt build up