Can anyone identify this creature?

[ntime60]

http://www.captivereefs.com/forum/picture.php?albumid=391&pictureid=3458

http://www.captivereefs.com/forum/picture.php?albumid=391&pictureid=3457

Should I be concerned? I have about 6-8 of them right now.

[jimsflies]

Not sure what it is...but nice photos.

Is it free swimming? My guess is some variety of flat worm.

[ntime60]

It appears to swim sort of like a squid. I put live sand in my sump/refruge last weekend and now I have these as well as a whole bunch of other free swimming creatures that are very small In the green picture you can see what the others look like in the upper right of that photo..

[stylaster]

It looks like a flat worm to me

[buk]

def a flatworm...i'd get rid of any you can find asap. if you think you have 6-8 you can bet you have 100

[Tom@HaslettMI]

Probably a flat worm. I don't know if it's a "bad guy" or not... my guess is probably not. The other organism is an isopod... harmless and fun to watch.

Tom

[ntime60]

Thanks for the input all!

I vacuumed the offending entities out.

I also took the opportunity to thin out my macro algae, which I found a small growth of bryopsis and promptly pulled that hunk of rock and put it in the freezer. I also moved a couple turbo snails to the refrugium.

The isopods are quite interesting to watch.

[MizTanks]

My Scooter loves munching on those Isopods :)

[Detroit Giant Bettas]

flat worms are bad, but i once saw a handful of these flying carpet looking things that Tropicorium had in there to eat flatworms that were the most amazing things i've ever seen, and would build a tank to feature if i had the money. I think it was a nudibranch.