What are these new Polyps appearing on ONE rock (Bad or Good) look like Colonia Hydroids but diff

[WallyB]

I looked all around and CAN'T ID these. Specifically that they have the RED center.

I have colonial hydroids in another tank, and I've always expected them to infest my 2nd tank (but for years nothing).

Now as this tank's water quality has gone up, these appeared on ONE rock.
Should I yank the rock (treat it) before it's too late.

THIS TANK IS (SPS ONLY).

What are they?

 

[Crabs McJones]

Strawberry anemone?

 

[WallyB]

Strawberry anemone?

Thanks.

I Found this http://animal-world.com/Aquarium-Coral-Reefs/Strawberry-Anemone
and found this https://www.reef2reef.com/threads/id-hitchhiker-anemone.38181/

Mine don't look like Strawberrry Anenomes at all (but maybe mine are juveniles ), but I doubt it. Look very different.

It's a loose rock. Bit tricky since two rocks are leaning on it, but from past I learned best to Yank and find out what it is later.

 

[WallyB]

Maybe a Christmas Tree Worm, but still doesn't look the same.

 

[WallyB]

Here is a really good Hitchhiker ID link with Plenty of Photo's (Nothing close to what I have)
http://chucksaddiction.thefishestate.net/hitchhikers.html
(I scanned all the Hydroid photos and not like what I have. Whew!)
Pretty disgusting worm section YUCK!!

What I have must be some kind of Worm. Or Coral Polyp.

 

[Maggie321]

I think they are really pretty!

 

[Tahoe61]

Do they retract back into a hole or shell when disturbed? At a glance I am inclined to think a type of feather duster. How quickly have they popped up, are they noticeably spreading.

 

[Gareth elliott]

Do they retract back into a hole or shell when disturbed? At a glance I am inclined to think a type of feather duster. How quickly have they popped up, are they noticeably spreading.

+1 they do look like feather dusters. I had them all over my tank first few months after setting up. Now i have a few near high flow areas but only a handful. When up close is there a tube they extend from? Its more visible when they retract, as they only leave the tube showing.

 

[WallyB]

Yeah, they are pretty.
They do retract, but can't see any tube at this point (they are Super Tiny and I'd never notice them if they didn't poke out of the Cyano Patch)
I need to get a closer photo (more clear/Focused) with circulation off.
If feather dusters then all ok (and explains a common phenomenon....When water quality get's good [good and bad things come to life] )
If feather dusters then they are the nicest I've ever seen.

 

[NakiFantaki]

I found one of these on one of my snails shell. It looked like a tiny feather duster but I’m not 100% sure. It does retract, but it comes back out very quickly.

 

[ChrisOFL]

Looks like your average filter feeder worm to me. Mine grow out of my bio brick which suggests to me they feed primarily off of bacteria in the water. This would also explain why they are growing out of the cyano in such large numbers.