Problem, .... help please

Hi Im new here

This is White Russian (Serious Seed) from clone
Indoor grow, in coco and some in promix bx
Veg under 2 x T5 54w each
Temp is at 77 F day and 68 at night
The coco was rinced but its not the problem because it appear in promix to!
I feed with Osmosis water + an hydro a/b nutrient, Gh Bio CaMg+, Gh bio humic Acid, and Gh BioWeed and some Roots excelurator in the begenning

Ph is at 5.8 with coco and plant in promix is at 6.2, ppm about 600
The problem seems to develop at 15 days at the growth stage....

I was thinking about a zinc def, or a virus, today I give her a foliar with some Zn and Fe

Help please!

Kinda looks like N deff.

for some reason after week 2 your ph changed. get a good meter and get it to 7. your right its zinc etc def from high ph. stop foliar feeding, better to correct the ph and solve the prob than pile nutrients on and make it worse.

Ok thank you for yours anwser guys, .... for now I use a cheap ebay ph meter .... I have the black combo made by hanna. I just need to change the probes. Go to buy one today

Thanks again

ok make sure its the rightkind of 'probe'

I am thinking micro-deficiency, probably a complex of them.

A little Iron and Zinc maybe some Sulfur. Probably Sulfur given a plant needs single digit ppms of Iron and Zinc, while requiring slightly higher levels of Su.

Your pH is probably an issue given the testing supplies you've listed. I'd get that dialed in right before doing anything too hasty. If you want a complete Micro supplement I suggest Organicare (Botanicare Organic) Huvega. Adding 5ml of that per gallon will supplement enough of the 70+ micro-elements a plant needs when using filtered water. You might not need it, but if you had an extra $25 laying around it is worth a go to enrich the filtered water. I like the stuff well enough.

From the way the yellowing on the leaf looks, could be a zinc issue or a magnesium deficiency. Here is a link that shows different pictures and gives ways to fix the issue:

http://www.icmag.com/ic/showthread.php?t=11688

I agree with noxiously looks like a magnesium issue to me.