I know alot of stuff grows in reef tanks, but what do you call this?

They are about the same size as my larger copepods. I haven't been able to match them up with anything.

 

I belive they are a type of jellyfish that will go away...I will get you a link for it...back in a flash....I remember now they are called Hydroids. Nothing to worry about
Danny

 

Look here friend....
Live Rock Hitch Hikers

Danny

 

I got lil jelly fish!!

 

They will die out though....I had them for long time....get a magnifying glass and watch em go towards the top and get blown around by the powrheads...they are cool
Danny

 

I got stung by my lil jellys
There's heaps of them now, like im talking heaps. Im not really sure whats going on but they're growing in numbers almost as fast as the copepods.
I only found the massive groups of them behind a rock when i reached back there to retrieve my mushroom which escaped the netting (i thought he would be happy all netted up). I felt a sting and thought i scraped a rock, but when i pulled my hand out, there was like 4 of these things on me, and heaps more on the glass where i had my hand.

I dont know if I should go Dexter on these guys or not?

 

i see ure from australia. do you get water from the ocean for your tank? ummm, i WOULD go 'dexter' on them. specially with all the things you guys have in your water that can KILL you! better to be safe than sorry later,.......box jelly, irukandji.......

 

well im from the south east so there's no killer jellys here, they live up north around the great barrier reef.
I mix up salt water using red sea crystals, so I dont think the jellys are too bad.
I'll still work out a way to perform genocide and not upset the tank with a mass amount of dead animals.

 

More likely the "sting" feeling may have been bristle worms...

 

whats that lil white thing next to them, looks like it has antennas