Black Brittle Starfish or Bristle worm??

[DudeItsADiscus]

We recently just bought 10lbs of live rock(7 days ago), and have run into some hijackers. We are farely new to saltwater, but very new to live rock and such. We've had our tank setup for about 5-6 months with plain rocks in it, a GSP, and a sailfin molly. We've been doing our fair share of research but can't find every answer to our questions. Our tank is a 29gal. with an emporer 280 on it and a Powerhead pushing 170gph. It currently doesn't have marine lights but it does have 60watts on it. We do feed the tank 2tsp of DT's photoplankton every other day.

Our list of other hijackers; a small shrimp thing (saw its head and thats it), a small crab, a featherduster, a coral of some sort, and this.. (you can see pics of the coral and featherduster @ http://www.monsterfishkeepers.com/forums/showthread.php?t=296508 )

What is it?
(The black spiny arm?)










Video: http://www.youtube.com/user/RidinDir.../0/-m9gQMtMRDo
Please help us understand what we have in our tank.

 

[sostoudt]

manjano anemone remove it.

feed the starfish some food he will like it

 

[sikoko]

remove the worm and above said anemone keep everything else

 

[DudeItsADiscus]

Why should the anenome be removed? What are the negatives and what would the positives be? We were thinking they might be polyps? Thanks for your answers.

 

[sostoudt]

Why should the anenome be removed? What are the negatives and what would the positives be? We were thinking they might be polyps? Thanks for your answers.

they are very prolific(reproduce fast) then sting other corals in your tank. they basically become a eye sore.

 

[DudeItsADiscus]

With us having nothing else in the tank at the time it wouldnt hurt to leave it correct? cause with us being new to this we were deff. exited to see everything we had gotten with just our live rock. also is it a danger to fish?

 

[sostoudt]

With us having nothing else in the tank at the time it wouldnt hurt to leave it correct? cause with us being new to this we were deff. exited to see everything we had gotten with just our live rock. also is it a danger to fish?

its probably ok to leave it, but it may be a problem later on if you decide to stock inverts.

my dad kept his one he found in his tank, saying he likes them. he would feed them too at first. now he has like 200. too each his own i guess

 

[DudeItsADiscus]

its probably ok to leave it, but it may be a problem later on if you decide to stock inverts.

my dad kept his one he found in his tank, saying he likes them. he would feed them too at first. now he has like 200. too each his own i guess

do you know what he would feed them?

 

[sostoudt]

do you know what he would feed them?

no clue, probably flakes or brineshrimp, maybe cyclopeezes(pretty awesome i recommend this product)

 

[DudeItsADiscus]

no clue, probably flakes or brineshrimp, maybe cyclopeezes(pretty awesome i recommend this product)

do u have a link for the product?
i have currently been feeding the tank DT's phytoplankton every other day.