It does sound like sun scald, except for the fact that it spreads quickly. I would expect sun scald to remain and for the pepper to survive.If...
Agreed, definitely ghost spot:http://gardener.wikia.com/wiki/Ghost_spot
Hmmm, I'd suggest a severe case of blossom end rot, how regularly do you water them? Have they got dry at any point?It's the closest match...
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