Septoria looks like a lot of things are you sure that’s not a pH, Cal Mag and/or nutrient deficiency?
… what makes you think it’s a fungus?
( I haven’t read the whole thread, if you can give me the bullet points why you believe it’s septoris? I have a link to where I had my issue I’ll put it up when I get a moment)
It’s near the end of this thread, I’m not a hundred percent sure it was leaf spot fungus but it did stop when I put the sulfur burner I noticed it the very first time I used it so I gotta think that it was but again it looks like a lot of other things