What Def is this? Dry, yellow and brown spotting

I've looked through the sticky posts, but can't really pin-point what my plants problem is.

Mountain Kush and Dinafem White Widow from Seed.
Week 4 Veg.
Pots: 4,7L
Soil: Canna Professional
Run off PH 6.4

Light: 250W CFL
Temp 22-24C (71-75F)
RH: 50-65%

Have not given any fertilizers until i noticed the problem yesterday.
I then gave it AN Grow/Micro/Bloom, AN Voodoo Juice and AN SensiCal (for cal/mag).
Everything at half strength. Resultet in EC1.8 (900PPM)

My two other plants are not affected. Barneys Farm LSD and Sour Jack.

Plant on saturday:

(White Widow)


(Mountain Kush Right after watering, it is wilting a little)

Plant on Sunday:

(White Widow)


(White Widow)


(White Widow)

To me it reminds me of Mag-def, but it is not really starting at the edges..
Anyone have any thoughts?

The Rest:

(Outer, Left: White Widow, Right: Mountain Kush. Inner, Left: LSD, Right: Sour Jack.)

between burn and camg imho i would say mag but i know it starts on the edges and it starts low and works its way up

hey man... do you smoke cigarettes?

edit: nvm

It's on the bottom leafs now.
It can't really be burn.. I did not add any nutes until after this started.. and the plants have been perfect until now.

It's the whole edge thing that makes me wonder if it's something besides mag.
I have soft water here (EC0.1, 50PPM)..
To prevent low ph, I added dolomite lime to the soil before planting, and also at 2 weeks (the soil started to go below PH6).
Doesn't lime add mag?

No cigarettes! Only sweet, sweet pot

Rootbound ,repot them.

I took them out of their pots, and I can't say they look root bound..

Could it be something else? That would be very convenient.
I've used 3 gallon pots before, but these are too tall for my grow-box. (29cm, the box is 90cm, and I also need space for the lamp).
The 4,7L are perfect in size for my box.

But I don't want to rule anything out, just cause it's convenient

i beleive that is a mag issue also secondary issue due from potassium def

shnazul23 said:

i beleive that is a mag issue also secondary issue due from potassium def

Click to expand...

It looks like you're right.
As stated earlier, I added calmag and nutes the day I saw the issue.
It has not gotten any worse after that. Checked the roots again today, and it does not look rootbound.

I'll keep checking the plants, and hope the nutes fixed the problem.

Thanks for the replies guys!