Hydroid or anemone?

[Llg]

Hello.

I have been watching this thing grow the last week. I am not sure what it is. I purchased a piece of live rock a few months back and lately, I have seen many new things like stometella and limpet snails, etc. This week, I found a patch of colonial hydroids that I quickly glued closed. This has been at the bottom of the tank in a space that I can't reach. I have a RBTA in the tank, but can't figure out what this is. Sorry if the pictures aren't the best. It is at a really hard location to get good pics.

 

[bradleym]

Try looking up "ball anemone " or "pseudocorynactis" and see if it's a match. They are a common hitchhiker, loosely related to the mushroom coral.

 

[vetteguy53081]

Its a ball anemone and although called anemone (due to patterns of balls) is actually a mushroom

 

[Llg]

Is it safe to keep with fish and snails?

 

[bradleym]

Yes, they are harmless as far as those tankmates go.