White fuzzy spongey.... things...

[Eclyps19]

Been QTing about 8 frags for the past couple months - when I first got them, I pulled off one or two of these things from a frag, but now I see them popping up on a number of other frags in larger quantities. They are almost always at the underside of the plug, usually growing out from between the plug stick and the hole in my frag holder. Here's a picture of the underside of a small paly rock.



They come off fairly easily, but I've never seen so many of them an I'm concerned that they are just going to continue spreading to the rest of my plugs. What are they, and what's the best way to get rid of them and prevent them from returning?

 

[JumboShrimp]

I believe those sponges are harmless filter feeders, but those are a lot for one plug. Maybe someone here does know what you can do about them, if they bother you. (Other people might like to keep them— biodiversity.). Best wishes!

 

[Eclyps19]

I believe those sponges are harmless filter feeders, but those are a lot for one plug. Maybe someone here does know what you can do about them, if they bother you. (Other people might like to keep them— biodiversity.). Best wishes!

Thanks - the QT is only 2.5 months old, so maybe it's just part of this particular tank's startup phase. I certainly don't mind them if they aren't going to kill my corals

 

[infinityends]

They look like pineapple sponges to me. Nothing to worry about.

 

[Silver14SS]

Looks like pineapple sponges

 

[Jake_the_reefer]

I've heard in a large concentration they can take nutrience from corals and eventually release toxins that hurt them. I had them and they dissapeared on their own. Strong lighting can kill them. Also I think my emerald crabs ate them but all in all they are harmless!!

 

[Katrina71]

They will eventually thin out on their own. Common in a newer tank.

 

[GThompson]

I used to have a lot of them but as everyone says, they disappeared on their own