Spots during flower

3rd week of flower and could anyone tell me what this is and how to fix

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You might find the deficiency on this chart, click to make it bigger and use the magnifying glass to zero in:



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K deficiency - Potassium

Looks like a Ca issue. CaNi would solve the problem, but...you're in flower and CaNi contains high amounts of N, which you don't really want at this point, so...it'll be a fine line. Good luck friend.