Unknow species

[patrick.harrison]

I have these species growing in my established tank. Can anyone tell me what they are and are they ok in the tank.

 

[NYreefNoob]

the one is blue sponge

 

[Treef]

First two pics are of a sponge, I have some in my tank and they don't seem to harm anything, have one growing right in the middle of a colony of zoa's. The last two pictures are I believe of vermetid snails, they are OK to have in the tank too...but they reproduce quickly and the sticky strings they send out to catch food sometimes irritates corals. As long as there aren't many of too many of them then they do a good job at catching stray food or dirt.

 

[KathyC]

As Rick said, the first 2 pics are sponge. They are safe, a nice color and show your tank is maturing.
http://www.reefkeeping.com/issues/2005-06/rs/index.php

The last 2 pics are of Vermetid snails. They won't harm anything but they bother some people by what they look like when the are feeding..kind of looks like a spider web that they let out and then 'reel' it back into the tube where they eat it. The size of their population is usually based upon the availability of food in the tank.
http://reefkeeping.com/issues/2005-01/rs/index.php

 

[patrick.harrison]

Thank you all for your help.