Looks like I have an anemone whether I like it or not: ID?

[apos]

So last night I was watching some new cerith snails do their work with a red light, and I came across something on the sand that startled me. It was what looked like a very tiny anemone moving its tendrils in and out, but it doesn't look like any of the normal pest species I can find online. Most notably, the ends of its tendrils have a little ball.
I can't get a photo because it's tiny and also seems to mostly pull in during the day (best seen in red light, which shines right through it)
It looks most like this: http://www.underwater-photos.com/pw035.html
But the tendrils are smooth not jagged, there's only one, and it's more clear than red, as well as the base of the tendrils being much closer together.
Anyone have any idea what this could be?
I had long ago decided no anemone's for me (because of the danger of them dying and nuking a tank for a newbie keeper like myself), but it looks like I now have one like it or not. Should I worry about trying to get rid of it while it's still small?

 

[perfectdark]

Sounds like a glass anemone of some type. Related to aptasia but in some cases arent as bother some because they dont reproduce as rapidly. There are some that are actually sought after because they are so nice to look at.

 

[lexluethar]

I second the idea it is a glass anemone. I would keep a close eye on it over the next few weeks, and if it starts reproducing at a rediculous rate then take measures to control its population.

 

[cprdnick]

Sounds like the ones I had, I left them in my tank, and they stayed there for about two years until I took my tank down. They never got any bigger, and didn't reproduce. They were kinda pretty when you actually got to see them.

 

[shrimpi]

most likely a hidden cup coral they come in different colors

 

[apos]

I've actually seen another one now, so either there were already two or the one reproduced. They have a red mouth at the center of the clear tentacles something like the mouth in the picture above. The tentacles look very different though. Could it really be a type of coral?

 

[morval]

thanx for that photo shrimpi

ive had one of those in my tank for 8 months, it came on a peice of live rock. now i no what it is.