@Zorro123, chlorosis on top means, in most cases, excess of Potassium and/or Phosphorus; but the leaf shows deficiency, from where you removed that leaf?
anyways, in the pre-flowering stage and at the end of it, if plant suffering from something, it shows it most at this stage, so don't try to much, just a little bit, sometimes doing a lot of thing is worse than just let it going as it was , but now I see u are giving your plant organic nutes, once in every week right?
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