Please tell me what this is!

Hey everyone I was wondering is this what leaf burn is? It’s on most of my plants and I can’t understand what it is. The only thing I did to all the plants that would cause this is neem oil. I sprayed all my plants with neem oil out in the shade during the day then I brought them back inside and put them back in the tent with just a t5 light on for 8hours before I turned my MH back on. The MH is only on 250watts also. So I just don’t see how my plants would be burned bit that’s all I can think of it being. Havnt gave them any nuits because they have been in ocean forest soil by fox farm and have been for over a month. So please can someone help me on this. I’ll take more pictures if have too. Thanks

I have seen @garrigan62 post pics of leaves like that showing nitrogen deficiency.

Looks too dark green to be a deficiency to me. Might be nutrient burn.

Looks like the start of a Potassium deficiency to me. Can you fill out a support ticket?

COPY/PASTE: This “Support Ticket” into your forum post.
Answer these simple questions the best you can.
If you do not know, or do not use something; Just say so = NA

Strain; Type, Bag seed, ILGM… name of strain:

Age from Sprout:

Soil in pots, Hydroponic, or Coco / Brand and type of Soil & Size of Pots:

How often do you water and how do you determine when to do so?

PH of water and runoff or solution in reservoir:

What is strength of nutrient mix? EC, or TDS:

Indoor or Outdoor:

Light system, size and height from plants:

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Humidity; Day, Night:

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Co2; Yes, No:

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