Leaf trouble DWC

[Space cowboy]

Hi all! So this is my first grow in 10 years and first shot at dwc. I've battled pythium and won, almost burned the girl, etc. The good news is I have caught it all early. The latest has me stumped, though. Any thoughts?

 

[Old Salt]

to the forum...

It may be Leaf Septoria, but I can't be sure. We need more information to help. There's a link in my signature block.

 

[Rifleman]

Looks like it could be pH fluctuations. How are you checking pH? If with a pen when was the last time it was calibrated? More info, and photos under white light would help w the diagnosis.