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Plastic changed daily - bowl,
No bleeding, not unless I tweeze the black stuff off then it looks like a scrape
He is normal everywhere else
It sounds like he has feline acne. The cause is not well understood but in some cases a reaction to plastic can cause it. Try switching to a glass or metal bowl and wash it frequently. Rarely are medications needed. Frequent cleaning and application of topical ointments when it worsens usually help. Here's a link with more: