Help i.d. please

[ciscomania]

I was looking at my tank today and saw this thing growing on one of my zoas. Can someone tell me what this is and if it's harmful to my tank? The picture is kinda bad but this was the best picture I have.

 

[Diesel]

Aiptasia if my old eagle eyes are seeing it correctly.

Btw, not a good thing to have, kill it painfully with either a Kalkwasser mix paste or some superglue right in the center.
Make sure you will guard the super glue till it hardens out in about 30 sec as maybe your fish will go after it as they think it's a snack and their lips will be super glued together, you're not the first one it happens too. :eek:

 

[ciscomania]

thanks for the help. I had a feeling that it might be aiptasia so I just detached the whole zoa frag disk from the rock and took it out of the tank. Does this mean I'm going to have a aipatsia outbreak in my tank now? This is the moment I dreaded, and hoped that it would never come. I made sure I dipped my corals everytime, but how does aiptasia start?