Hey bro it looks like some calcium or manganese deficiency... If you are using RO water you can add some cal-mag to your water, but other thing that you can is to make sure that your phmeter is adjusted and reading properly, sometime plants can't absorb some nutrient because you are working in the wrong spectrum of pH.
And like our friend in the answer also said, why not start a diary? You could have so much more help from the community :)
Good luck!