Please help me identify my problem - Yellow Leaves and Brown Spots

I am growing 3 types of plants, sfv og, west side og and skywalker og. The skywalker og and west side og is loving the nutrients. however the sfc is not doing so well. The leaves are beginning to turn yellow and some of them have brown spots. Here are the attached pictures.

Running on Lucas Formula Gh Ratio 0-8-16 (8ml micro 16ml bloom per gallon).
Ebb and flow system under 1000watt hps

looks like nute burns or over watering or maybe both......

by looking at your medium, there might be overfeeding. I would recommend to check the sticky from Uncle Ben and see which situation applies the most in your case.


Cheers!

looks like nute burn and heat stress. what are the temps at? how far away is your 1000w?

Hi thanks for your guys responses! I was using 6inch rockwool ever since it was a little clone (3 weeks ago). Now the rockwool is in a gro pot with coco. I water about once a day.

Temp of room is avg 70 degrees and the light is 2 ft away. Water is between 700-1000ppm. Do you think nute burns the problem?

it looks like nute burn to me also because it's mainly on the edges. The curling may be caused by heat stress and or poor humidity. Sometimes you will get black spots if your temps and humidity go from very cold to very hot temps rapidly and repeatedly.

ppm is waay too high for that size of a plant. Lower it to 400-500ppm and you should see some recovery