Silvery streaks and small black specks on the upper leaf surface usually mean thrips rather than a nutrient issue. They pupate down in the medium, so treating foliage alone leaves half the population untouched, and the pest pages on https://kushindicaseeds.com mention sticky traps and soil drenches as a combined approach. Damage looks worse than it generally is. A small population on a healthy plant in veg rarely affects the final result.
