The only solutions I've heard for blue clove polyps aren't reef safe (they might kill off other things in the tank), but the most common treatment I've heard is Fenbendazole. Someone else used Lugol's Iodine, but they also lost some corals from that. Some people say kalk paste or super glue may work, but I haven't seen many people reporting success with it. The links below may help:
Does anyone know how to kill off invasive clove polyps? They’re starting to spread and envelop my acans and I don’t want them swallowing my garden.
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A few years ago, I purchased a rock that had some beautiful Space Monster zoas on it. It also had some Blue Clove Polyp on it as well. I saw the BCP, I knew it was there, I really didn't worry about it at all because I had no idea what it could become. Fast forward....its now everywhere. Its...
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