ID: White things....worms?

[bevo5]

Hi all - I'm sure this is an easy one, but I've had these growing on one specific rock for a while now and figured I should ask what they are. I thought spaghetti worms but they seem to move or retract or anything like that.

They all just hang out under a big hammer that I've had for about a year.

Thanks.

 

[saltyfilmfolks]

http://www.lionfishlair.com/hitchhiker.shtml
scroll down to sponge #3 and bryozoan

 

[bevo5]

Great list there. It's hard to tell with these. They don't have any type of feather feel or spongeness to them. But I guess as long as they don't seem like trouble to people then I won't worry about them. They've always just stayed in one place.

On a side note. While poking around the rock I found my tanks first aiptasia! It's s big one hidden behind some rocks. Up a year and never seen one. I guess he snuck by. I'm gojnf to get some aiptasia x in the morning. Then a peppermint. But the peppermint I had before are my acans.