Maybe copper based fungicide spray and or
neem oil. Also septoria if caught early requires all damaged infected leaves foliage roots plant matter to be removed. Usually it's from diseased soil or seeds? Highly contagious and very hard to get rid of in later stages of production. If caught early and all infected matter is removed. And appropriate needs to disinfect the grow space room walls floors area. As septoria spores can be around for a year or Two, and it will be stubborn as fuck if it gets to far! There's a few products to choose from what works best for you the situation and of course your girls is up 2 you man. I can't remember but if you're humidity is stable it'll help with the spores dieing off also. I'd go for that copper based fungicide myself gromie. And of course them trace elects might have enough Copper to do the job but that's uo to you man.