It sounds like it could be bacterial spot. Though it's a bit hard to do a diagnosis over the 'phone', if it is spreading to your other plants, I'm afraid you're toast. You should immediately separate your chiles by as great a distance as can be done, destroy the infected plants, discard the soil and all crop debris, clean the containers with a mild solution of bleach, and try again. Bacterial spot (as well as most of the other leaf spots) are caused by a fungus that lives in contaminated soil and crop debris (fallen leaves). It will over winter and affect next year's plants as well as spread to everything around it. Bacterial spot most often develops from moist or damp conditions. Don't shoot! I'm just the messanger. -Jim C Mild to Wild