Live Rock Hitchhiker ID

[bloojeanz]

Does anyone know what the following creatures might be that arrived on my Live rock? they were tube shaped, about 2mm across and maybe 5mm tall, opaque in colour. Now they appear to have opened out into a flat circular shape with a serrated edge all the way round and a small darker central 'hole' ???? Sound familiar to anyone?

Also I have some brown growths that look like branches ( just like little twiglets ) all over my rock which are now sprouting leaves, can anyone suggest what sort of plant (algae) this might be, thanks in advance !


bloojeanz

[Satchmo]

The leafy twigs you see are most likely sargassum. It's a macroalgae common in new tanks w/ LR. You'll see much more of that sprouting out, then one day it'll just all die away.

Don't know about the first one. You had me thinking colonial feather dusters until the serrated edge thing. Got any pics?

[bloojeanz]

Thanks Satchmo, they are too small to photo at the moment, but they are growing quite quickly, too quickly for my liking! And I am sure there is more of them too!
I hope they aren't some sort of pest anemone, that would be just my luck!

bloojeanz

[DeltaUguy]

It sounds like to me that you're describing Aiptasia. Its a nasty pest anemone that stings corals and spreads like a wild fire. If they move around some then that's what it is. Pepermint shrimp eat them. There was a thread with a pic of one not too long ago.

I think its pic number 2.

http://www.aquariacentral.com/forums/showthread.php?threadid=4158

[bloojeanz]

They are polyps, I just saw the exact same thing at my LFS. Thanks anyway!