TOTAL buzz kill here ... I got completely blindsided by this too.
My CBB passed away last night. Had him nearly 3 years. I'm truly amazed at how quickly fish "check out" when their time is up. He was fine up to about his final 3 hours.
Otherwise, my carpet was looking fine this morning, but literally, I'm sort of crying here. He was such a favourite fish. And given the current state of CBB's that I keep hearing, I don't think I will try another.