If a plant has roots and there are fungus gnats anywhere nearby then they will try to invade your soil. Even with good watering practices. I've seen them try even with a SIP setup with precise watering volumes that keep the top couple inches of soil dry. A healthy thriving rhizobiome will keep soil born pathogens in check.

Thanks everyone for your suggestions. I’ve decided to change watering practice, use shallow trays under fabric pots and removed the septoria infected plant. I fill the tray a couple times when I water allowing the bottom to absorb some water but not enough to keep it moist all the time. Everything is in late stage of flower so I’m not going to use any chemicals, including peroxide. Once I dry and trim the buds the gnats should be gone. I’m not thinking that they have any psychological effects or good flavor. My focus is to remove all gnats from apartment and tent and to use a better soil that discourages gnat larvae. I will also discontinue the self watering bases and stick with using trays so I can bottom feed a smaller amount. The plant I removed with septoria is still budding well outdoors. I’m wondering how much effect the septoria will have on flavor and potency. I’ll keep everyone posted.

I only have to use it if I get a really bad infestation of fungus gnats but I use good soil I feel the same why ruin your soil with synthetic fertilizers but don't think the fungal disease is from soil gnats

Organic agriculture strictly prohibits the use of synthetically produced fertilizers, pesticides, herbicides, and other synthetic chemicals. T