Soil Growers:
1. Are you growing from seed or clones? Seed and clone in this room.
2. How old are your plants? The most sick plant is 5 weeks
3. How tall are your plants? 16-20"
4. What size containers are they planted in? 3Gallon
5. What is your soil mix? I honestly dont remember, black gold i think.
6. How often do you water and what type of water do you use? PH tap water, usually 2-3x a week.
7. What is the pH of your water? I tend to go between 6.2-6.8
8. What kind of fertilizer do you use and what is its NPK ratio? Fox Farm line 12x bottles or whatever
9. Do you foliar feed or spray your plants with anything? I just started a couple days ago..
10. What kind of lights do you use and how many watts combined? Mars Hydro 2000
11. How close are your lights to the plants? 16-18"
12. What size is your grow space in square feet? 3x3
13. What is the temperature and humidity in your grow space? 75-78 consistently per the app
14. What is the pH of the soil? Took a sample this morning at 6.4
15. Have you noticed any insect activity in your grow space? no
16. How much experience do you have growing? 0

I have a small window to either feed them fully or just water+calmag.....what is everyone's suggestion?? I have two opinions from grower friends and one says mag def and other says nitrogen tox...

Just water cal mag. Seems like you posted pics of a few different plants, the top one to me looks like old damage or possible insect or light burn(possibly spraying them with lights on). Next two clear sign of N toxicity and possibly hungry for some P. Third one looks strange but the lighting is throwing a proper visual diagnosis off. Final picture same as the first.
Did you spray with the lights on? What does the entire plants look like? First and last one, do they have this symptom all over or just on that leaf, and how long has it been like that? Is it progressing and where did it start? Middle two, have they always been that dark?
Whats the FF feed your doing and at what PPM? Grow big i assume?
How did you test your soils PH? Do you have a PH tester? A run off test will tell your PH

Thanks for your reply:

Yes different plants, different problems. Same feeding lol

I did spray with lights on - I will not do that anymore. What's procedure for that? In my veg im on 24 hours so they don't have a time without light. I can spray the flower tent after lights go out?

I will advise today with pictures updates when they wake up at 7pm tonight

Reduce your lights to 18/6 or just use a small lamp

A lotta folk run shorter lights on for veg, cuz A; its not needed plants like people need sleep and B; save power. 18/6 16/8 even 14/10.
You have the ability to control how much your feeding, plants need individual feed cycles. When you spray with lights on the water droplets refract the light burning little holes/spots onto the leaves.
What are you spraying and how often? Why?