Anyone Identify This Thing

[JOANN]

Thanks Guys I will look up what these things are.

 

[Dave3112]

yes all rock in sump no sand and yes filter sock as well

Sorry, I just saw where you replied. If it was me, I would take all the frags out of the tank and dip them (I prefer Bayer) and try to see if any come off of the corals. Then really stir the water up good in the frag tank to try and get any free floating ones down to the filter sock and change the sock out. Then just observe closely and see if they come back. If so repeat with the frags and then if they keep coming back I would look at an extended FW dip/soak of the LR in the sump. I know that all f that may be a little over kill, but I had AEFW once (NOT WHAT THIS IS!!!) and I am just over cautious/paranoid now... Good luck and keep us posted!