Snow White+Zensation, 400w HPS, 2/3 weeks from seed.

Is this a nutrient burn/deficiency problem or is it a light burn problem? If its a deficiency I might just switch to chemical fertilisers, Iv had not much luck with organics. Any help appreciated.

EDIT: Could my water pH be too low at 6.2?

the curled edges in #3 make me think light burn because the ends of the leaves arent burnt and thats the first place nute burn shows up

400w is about 12inches from the canopy with no fan..really low ambient temps here at the minute tho.

I looked again and stay with my first diagnoses of light burn as the leaves are fine. could it be spilled nutrients and just a stain on the leaves?

and I am remiss, what kind of soil are you using?

Biobizz All-Mix with extra perlite, just transplanted from small maybe 10cm pots to 10L pots.

EDIT: The roots had started circling on 5 plants when I was transplanting but I "agitated" them lightly...Id say I loosened up the root ball with my fingers as I was of the understanding this encourages them to grow more?

your pH is spot on so IDK, it dosent look like nute burn. give it some time and see what happens

Reckon I should give a bit more distance to the light?

I have a Zensation going as well, touchy girl. She Likes high N to get her a darker green, and extra calcium, I had more luck with pH in the 5.7-6.0 range btw Hydro setup, got burning above 6.0 just like yours.
Growing now, watch the progress https://www.rollitup.org/grow-journals/396216-lilly-zensation-moc.html

Shes got a nice smell tho, very unique.

Here BTW surprised you havent found it already. https://www.rollitup.org/marijuana-plant-problems/216537-self-diagnose-your-plants.html