Aiptasia or something else?

[Madkix]

This was the best photo I could get of it, sorry.

I noticed it on the sand bed a few days ago and it seems to have attached to this rock. I'm not sure where it may have come from since I haven't added anything to the tank in some time.

 

[PokeFish]

yeh looks like an aiptasia or some sort of mojano anemone

 

[Madkix]

Any chance it's a Triactis? I have/had two pom-pom crabs in the tank, though I haven't seen them in some time.

 

[cpoynter]

Any chance it's a Triactis? I have/had two pom-pom crabs in the tank, though I haven't seen them in some time.

If it is, you might want to carefully remove it. The Wikipedia page says it delivers a nasty sting.