In scenes aired on last night's show, the pair were seen talking about nominations after Alicia said she suspected Calum of picking her.
A conversation ensued in which Alicia called Calum "two faced" for nominating her, and he said he just felt he talked to her less than anyone else.
Calum eventually said: "I told Big Brother I was reaching when I nominated you."
Housemates were later gathered together in the living room, where Big Brother revealed the conversation to everyone.
After dictating the entire conversation between Alicia and Calum, Big Brother said: "This is a clear breach of rules regarding the discussion of nominations.
"Big Brother takes rule breaking very seriously.
"As a result of Alicia and Calum's conversation, housemates will no longer be able to use hairdryers or straighteners until further notice.
"This will include preparations for tomorrow night's live show."
Alicia and Calum both apologised.
The housemates are expecting one person to be nominated this evening, unaware that Big Brother has cancelled the eviction due to Alexander O'Neal's exit from the house.
Instead, we'll get a live nominations twist courtesy of Emma Willis when the episode airs tonight.
Alicia, Perez Hilton, Katie Hopkins and Nadia Sawalha were all nominated for eviction this week. Those nominations will roll over until Friday night's live eviction.
CBB housemates with no makeup!
Copyright: Channel 5
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