I've just treated it for iron deficiency all the leaves were yellow now they are green again so that's good but now these little spots only so much googling you can do.
Looks like thrip damage. Best way to beat them is with diatoms, aka diatomacious earth. Tiny fossils, shred the large and cut the adults up well too, Kills most crawlers. Dust the whole planet with it. Dust the soil with it. You can find it at most garden stores, or pet stores. Get the food grade , nothing else is needed. Even if it's nothing at all you will not harm the plant, it will be a preventive measure.
Makes sense as there is a few bug like things crawling around my veggie garden (place of storage for pot plant) black and hard shell looking about half a pinky nail size.
