White Dots on leafs like paint drops?!

Avoid to water your leaves.

Best guess is light burned or nutrient burned directly on those spots from being wet. Your pics show wet leaves.. this can be the result of that

even in super soil you don't want dry pockets... it'll wreak havoc on your substrate's nutrient balance in those areas. Don't try to give a round number you like. You give enough to ensure the pot is fully wet. With super soil best to have as minimal runoff as possible. If you water at same pot-weight, then it'll require the same volume of water to get fullly wet each time, give or take your ability to weigh a pot by lifting it slightly. You can further dial in howmuch to give and confidently reduce runoff waste with no repercussions. With super soil i don'tknow if you wait for top 1" to dry or preempt it a little bit? whatever the common suggestion is.. google will verify any differences between soil and supersoil watering habits i am unaware of. The minimal runoff is common sense, or you waste your supersoil contents. So, this could be substrate related due to your irrigation habits... even if it didn't happen the first week... this sort of thing is a slow simmer that builds unseen then fucks with your grow at a later date... so you think what you are doign is fine and it's difficult to associate the repercussion with the cause because they are separated by so much time. Other possibility.. did you drip anyting on it? could have burned it that way too. Easy to eliminate that possiblity. So, after that i'd guess root issue due to watering habits. Water properly and it should abate. Those spots will never heal though.