New Hitchhiker

[RedTail87]

I've been watching these for a few weeks now and haven't noticed them cause any harm to neighboring critters.. I've tried poking them before and they don't respond to being poked. Does anyone know what they are? I was going to leave them alone but they are reproducing and I didn't want them to go crazy if they were bad critters. Thanks!

..... Ignore the cyano.. I was blasting it so it's kind of all stringy and annoying.

 

[catran]

Looks like a hidden cup coral or ball anemone. Both are harmless. You can scrub them off with a toothbrush if there are too many. I kept my single one and it hasn't grown or spread.

 

[die4lulu]

they kinda look like feather dusters to me... cause they are coming out of a tube, right?

 

[livebait]

I believe they are colonial hydroids.

 

[Blndbunny]

+1 on the hydroids, I have a number of ball anemone and hidden cup corals, they all react when they are poked at

 

[RedTail87]

I suspected they might be Hydroids but wanted to get more opinions. Thanks you guys!

 

[CarmenH]

I have colonial hydroids and they absolutely retract when touched...

 

[RedTail87]

Do they? These didn't. :/ I dunno, I covered them in Aiptasia X anyway and the halloween crab ate the left overs.

 

[die4lulu]

hydroids was my second guess

 

[Boomer]

They are Hydorids. You can tell by the "ball" at the center. Similar to these

 

[StirCrayzy]

I say ball anemone. Judging by those pics. Hydroid centers look a bit different than the samples shown.
I have a few of these myself.
I Never poked them, they retract spontaneously, have doubled in #s this last year, and seem to not bother anything.