Hitchickers on live rock (filter feeding invert)

[Izcuacho]

hello;

I bough a use JBJ 45 that came with live rock and looking around I found critters attached. Closely looking at them they seem to be some type of filter feeding invert because it has a mouth on each end (I'm guessing water passes through them). They do inflate and deflate to the tough so they are alive. The mouths are interesting king of a lavander color inside with purple lines. The outside looks like dead sponge dark brown close to black in color.

I have 2 one about 2" the other close to it about 1 1/2". I'm posting a cpl of pics I could take to see if anyone knows what they are (it's right behind the gorgonian).
Thanks

 

[clsanchez77]

Awesome rock, way under appreciated these days. That appears to be a tunicate to me. They do not inflate like sponges but are filter feeders, so your assessment appears spot on. Unfortunately, I lost my one big one after a little over a year, but was proud I kept him a year. I have had the best result with the Florida rock when dosing phyto and oyster eggs. If you can do so, you will find some of the natural corals will grow out of the rock. Nothing to frag about, but very cool to grow your own and have the fill some voids.

 

[Izcuacho]

Thanks; as long as they don't harm anything I'm good with them. I bought the tank used and came with the rock it has a bunch of fan worms on it and a bunch of small serpent stars inside which are fine u can see there arms sticking out all over (but good cleanup crew).

I do feed phyto and oyster eggs and mix it up every other day; I have a a few gorgonians and a cpl of sponges so I feed the tank to keep them and my copepods happy (that is a seahorse and pipe fish tank) seahorses are captive so they eat mysis but pipe fish spends all day on the glass picking copepods.

Thanks for the description now I know that's a tunicate.