I'm getting my second for my tank. I've got a blue who is hosting a single Clarkii. My other two Clarkii need a "friend," since this single one won't let them near it. I'm hoping that the pair will host.
They're interesting animals. Yes, they're at the top, but they do what they were meant to do. If a fish wanders into its tentacles, they get stung or eaten. Just ask my Humu-humu. He went after some food in the anemone's disk and got stung. He's recovered now and stays away from it. A bubble tip, which is supposed to be less aggressive, actually killed my mandarin and a small tang. Happens in the tank, happens in nature.