Help!

[storkmpj]

I thought that these guys were OK until they have taken over my tank and killed most of the Corals. Please help me get them out!
I don't know what any of these are, but I don't think that they are good. The last pic is bad, but they look like tiny feather dusters.
Thanks.

 

[bigarn]

The 2nd pic is a vermetid snail ... harmless filter feeder. They put out a stringy web to catch particles in the water.

 

[c_thru_u]

None of what you're showing would be causing any problems. I think something else is causing your problem.
The first pic looks like a strawberry anenome and the last pic looks like a feather duster I think.

 

[spanko]

First picture looks like a Pseudocorynactis sp.. A corallimorph much like a mushroom coral but with tentacles like an anemone.

 

[storkmpj]

OK, but can having a bunch of these guys hurt? I have over 100 of the little feather dusters and maybe 20 or 30 anemone things.

 

[spanko]

The feather dusters will not hurt. If I had 20 or 30 Pseudocorynactis I would begin to get some of them out myself. I have maybe 3 in my tank that have not really grown at all over the last several months so I am just leaving them and have had no problems. They are isolated for other coral though.