What is this? video inside... white whip thing

[blackwagon]

The base looks like some crushed coral built into a tube. They usually pop out when I feed.

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[devimik]

Digitate Hydroid. Some say they damage corals, but I have them in my tank and have seen no real harm. They do cause my zoas to close up briefly, but no lasting damage. Makes sense that they come out when you feed. I've read that injecting boiling water at their base can kill them, but haven't tried it.

[blackwagon]

I thought they were something else and read that I could just crush the base and they would die but they are popping up in a couple different places now. I'll be boiling water very soon before this gets out of hand.

Thanks for the id.