Rust Spots affecting multiple plants

Does anyone know what's wrong with my plants. They keep having these spots that Red and dark purple on my gdp and they keep spreading. They usually start on the lower leaves then move up but on this pic of the gdp is starting at the top. I read that it could be a fungal disease but idk which one and idk how to treat it. I need some help. This has been happening during early veg and this is the first plant that's later in veg that's gotten it. They aren't yellowing first so that might cross off leaf septoria.

Looks fungal ( black spot ) - you can get Fungicide 3 ( Garden Safe brand ) available on amazon and various big box stores.

Fairly common issue in gardens ( tomatoes etc. )

Read label .

That would fix them? Thanks a bunch it's been a real nuisance

Could it be my soil. I use the promix yellow bag and this last time i noticed some white spots when i opened it. I didn't think too much of it though