FIRST TIME GROWER Deficiency - PLEASE HELP

Hello everybody,

I have stumbled into a problem and i`m not quite sure how to fix it.
I read countless forums but i still can`t make out what kind of deficiency this is.
I`m thinking either its Magnesium or Zinc.
I really dont want to apply the wrong treatment, that`s why i desperately need your help.

Grow info:
What Strain is it?
BIG BUD 85% indica from Sensi Seeds.

How Many Plants?
6 plants

Is it in Vegetative or Flowering Stage?
Flowering 2nd day.

Soil or Hydro?
Hydro, NFT system, 60 l reservoir.

Reservoir Temperature?
20-22 Celcius

Size (Wattage) of Light?
1 air cooled tube 400W HPS.

Temperature of Room/Cabinet?
25-27 Celcius

RH of Room/Cabinet?
50-60%

PH of Medium or Reservoir?
5.2 - 6.0 on average

Any Pests?
NO

Type and Strength of Fertilizers used?
Using Canna nutrients.

Seems like nitrogen deficiencies.

Looks like a couple tips are burned. Big fuckin deal. At least you know your nutes are working.

Wait till you're 6 weeks into flower, you're going to shit yourself.

Maybe the pictures ware not good/clear enough

large res