Just FYI, fungicide is a preventative. Once you have symptoms of a fungus infection, fungicide won't necessarily kill it. You might be seeing bacterial leaf spot. MIght just remove tha affected leaves. But protection for other uninfected foliage can be achieved with copper or chlorothalonil.

Hard to tell but that second pic looks like they could be sitting on concrete. Are these plants outside? It might just be sun damage. If not then it could also simply be a magnesium deficiency. You say the potting soil *could* be previously used and nutrients don't stay in potting mix forever.

There is no mention of you fertilizing them, nor do you mention what kind of growing conditions they are in or care they have received up until now so it's really all just guessing at this point...

Rodney

Growing inside 100% temps 68-78 watered from bottom. I planted from seeds. No fertilizer until 2 days ago (miracle grow potting soil).

Dan good point about not stopping it, I keep forgetting that. I pitched the 1 plant seemed like a no brainer - I had a few extra. Most mature leaves had it bad. Going to trim other leaves and spray immunox then in a few days daconcil.