Id please?

[erayk1]

I just found these after moving my rocks around a bit. I have fish and corals in the tank. Anyone have any idea what these little guys are? They are about the size of a pencil eraser.
http://farm4.static.flickr.com/3144/2301408374_fc42934417_b.jpg

 

[rssjsb]

People call them anemones, but they're actually related to mushrooms, I think. I've got them in several of my tanks.

 

[taylor t]

I've got those in my tank...I'm not sure what they are, but they can move from one night to the next. They come out more at night, looking like a court jester hat, turning into a ball in the day light. They retreat fast, like an anemone, so, my guess (and it's a guess) is they are an anemone. They vary from small eraser size to dime size. Had them for years.

 

[shiggs]

They look like little bubble tips

 

[NirvanaFan]

They're considered mushrooms I believe. I've got them in my tank and never have had a problem with them. I like the way they look. Google corynactis if you're looking to find more information. I'll bet that will turn up some info for you.

 

[ginger7286]

Whatever they are they are cool!!! The are shaped like the sun cup coral, but movement and retreat would suggest they are coral or anemones. Ver cool!

 

[bcribbs]

Look like Pseudocorynactis to me. non-photosynthetic, related to mushrooms as rssjsb and nirvanafan stated. check sprung and delbeek's reef aquarium volume 2

 

[Flighty]

I think those are Strawberry anemones - Corynactis californica

 

[c0mp|ex]

i have these too. are these safe or will they take over?

 

[traveller7]

Corynactis species, not likely C. californica though which is cold water.

Small, and fairly harmless in my experience. I have a batch in my breeder tank with some fairly pricey clowns and have no worries.

 

[livingcorals]

Traveller7 is right.
Form of aptaisia to some call it a ball tip anemone. Can be as aggressive as the aptaisia and get out of hand fast.