clear tube like things (vermatid snails?)

I have had them for some time, however it seems like there are more now. I have had many problems with corals and I'm wondering if these might be the problem. Also I have noticed spider web like thread in the tank, however I have never seen the thread coming from the tube.

 

looks like pineapple sponges there not vermatid snails

 

added closeup

on more pic that might help

 

I have seen these in my tank as well, and would like to know what they are. Don't seem to be causing any trouble.

 

Not vermitids.

Looks like a sponge.

 

They look like pineapple sponges to me to,if they are,there harmless filter feeders

 

I have many and they are harmless.

 

ok im sure they are pinapple sponge

I saw another picture on this site and it looked identical. So ill let them be and enjoy the benefits they provide. Thanks all.

 

Those don't look like vermatid snails, but the spider web like things are vermatid snails (so I've been told). I had some in my tank and I was told that the vermatid snails release those to collect food. Pretty neat! But I think they can be bad for corals...

 

I can't get a good enough picture but I have some of those sponges growing on the bottom side of live rock that are the size of my thumb. They will usually only grow in light deprived areas. I have never seen them grow in direct light situations.

It is a filter feeder. If you have alot of excess diatrus they strive, the lower the load on your tank they disapear, it actually is a good sign if your over feeding etc. Heck I have had them inside my Protien skimmer before.