Have something growing on my live rock

I have three of these little things that have showed up on my live rock. They are really tiny, too tiny to take a clear picture of (I tried). I'll describe them the best I can.

They are white, they have a root that's connected to the live rock with a little circular piece at the top of the root, then lots of tiny little tentacle pieces coming out from the circular piece.

I got the tank from my mum and have only had it here for three days so I'm super curious as to what they are.

 

Sounds like worms to me


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I am here: http://maps.google.com/maps?ll=33.496295,-112.397161

 

Sorry do they retract?


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I am here: http://maps.google.com/maps?ll=33.496390,-112.397133

 

probably little feather dusters.

 

Possibly aptasia.....

 

very true, apt and tiny dusters look similar.....good point

 

Sounds like pineapple sponges:

pineapple sponge reef tank - Google Search

 

Anything like this?

Redirect Notice

 

This is the best pic I could get of it, hope this helps a little.

 

hydroid maybe?