Please Help ID

[Keith P]

Now what do I have?!?
I found these things growing behind a rock (the thing in the shell and on the bottom left of the shell). They have clearish short tentacles with a ball shape thing on the end of them. They grow in dim, low flow areas. I pulled this shell out from the back of the tank for a better pic:

 

[Domboski]

I was once told they are called glass anemone's but that is a term commonly used for aptaisia. I think they are more likely some type of clubbed tip anemone but I can not find info for you. Either way they will become a nuisance.

 

[KathyC]

How many of these are in the tank Keith?
If it is the same thing as in my tank, I have just the one and have allowed it to continue growing for about 1 1/2 years (grows very slowly). During the day it looks like a small white jelly-like mass but at night it opens up and the top reminds me of a 'jesters hat' with shortish clear arms with tiny white 'balls' at the ends. It hasn't reproduced or caused any issues. I believe it is a tunicate of some sort from past research but can't locate it's proper name right now.
I'll try and grab a pic of it (late) tonight.

 

[reefman]

majano

 

[Domboski]

This is what Majano looks like: http://www.melevsreef.com/id/majano.html