I am growing six indoor plants all seem to be doing well except one. Little yellow spots on bottom leaves. Checked PH its fine. Plants are in basement with high humidity and noticed Gnat looking bugs flying around and landing on leaves. Top leaves doesn't seem effected and new growth continues any suggestions.
It's definately the gnats, You must kill them immidiately, I had a similar problem with thripes and I hand killed them all. If not buy lady bugs or a tomatoe insecticide. Peace.