Anemone id

[Kitsune_Gem]

This little guy just showed up one day in our tank. We have not added anything new into the tank in about 4 months, and he was not there that I could see. I don't mind him, as long as he is not going to hurt anything.

One week ago...

Today..he's about the size of dime, just a tad smaller. He's grown alot in a week time frame.

 

[m758b033]

I am not entirely sure that is an anemone. Maybe a mushroom or sponge?

 

[Gig 'em]

It's just a common hitchhiker anemone. Won't get any bigger than that or color up really. They aren't pests or anything

 

[bradleym]

Look up pseudocorynactis. Or corynactis, but usually they are the first one. They are almost always harmless.