... sorry I forgot to mention, 2 plants are affected the others are ok. Also, most the leaves on top of these 2 plants are affected.
Sorry again, these are not black, rather dark dominas.
They had not to much light or fertilizer, PH value is 5.6, temperatures ok and so on, every thing seems to be ok. Every plant grows under the same conditions but 2 of them are diseased.
I'm a grower for about 33 years, but I'f never seen something similar
Hmmm. Well, you have a lot more experience with Cannabis than I, but my first thought was that perhaps something splashed on the leaves (like fertilizer) and it was perhaps isoloated to a small area. Now I can't help thinking it is some kind of disease (like mosaic disease) and it my be best to isolate the two effected plants so it doesn't spread.
I was then not sure if it all related with this bug i lost alot of leafs with this, i stop eating my plant with Neem tee and spray.
but i must say at this time i had an ph problem.