Is this Ball Anenome or some type of Sponge?

[HumuhumuFan]

This is what they look like when retracted, for lack of a better word:

They are very small, maybe 1cm across. This is them open:

This one is sort of open I guess:

When I pulled the rocks out they looked like zits. They are also slimy to the touch.

 

[MoshJosh]

Looks like a ball nem to me.

 

[vetteguy53081]

This is what they look like when retracted, for lack of a better word:

They are very small, maybe 1cm across. This is them open:

This one is sort of open I guess:

When I pulled the rocks out they looked like zits. They are also slimy to the touch.

Its a very pretty ball anemone and the ball is given its name do to the look of tentacles from series of balls but is actually a mushroom and safe as well as desired by many due to their pretty colors

 

[HumuhumuFan]

I thought I lost them when I took down my tank but a few managed to stow away on stuff I was saving I guess!