Is this a mushroom/ What kind is it?

http://www.3reef.com/forums/members...-reef-picture6318-feather-duster-mushroom.jpg

 

if you are talking about the thing in the middle i would say its a feather duster or you will have to tell us were in the pic to look

 

its down on the lower left, i know what the feather duster is....the mushroom thing is down on the lower left by the piece of rock that looks like a log it is brownish looking

 

On the left side of the shot, the object with green specles....yes it is a mushroom coral.

 

so weird thing happend, I took this picture last night and I went and looked in my tank a minute ago and now it is gone haha, do they move around or did something in there move it?

 

Yep, they can detach themselves from rocks. They'll float around until they get wedged between/under rocks etc.

 

+1 whippy. Yes they can and will move if not happy where they are.