Aptasia?

[Cole2h2]

Any id on these little guys, they retract back into rock when touched

 

[WheatToast]

The pictures are a little blurry, but what you have photographed and described sounds like Aiptasia.

 

[Sleeping Giant]

Yup aipstatia

 

[WheatToast]

The pictures are a little blurry, but what you have photographed and described sounds like Aiptasia.

Actually, I take that back. I saw on your other thread that this "Aiptasia" appears to possess a hardened tube. In that case, I believe you have Colonial hydroids. Mine do not seem to bother anyone.

 

[Elitecorals]

If I were you I would try to get rid of it

 

[Fish Think Pink]

photo isn't that clear, but seems like aiptasia as no column/tube appears visible to me based on above photos. Either way, agree smother/kill/remove. Both colonial hydroids & aiptasia if broken during removal will regrow into more - aiptasia scrubbed with toothbrush in tank into zillion bits becomes zillion bits. Franks F-Aiptasia is a great smothering product; I've used it and works awesome on aiptasia.

Unfortunately my tank has a zillion colonial hydroids... people keep saying they clear up on their own... I'd need 1-2 gallons of Frank's F-aiptasia for my hydroids. Hindsight is 20/20 - IF only we had smothered them the day they showed up, like we did with aiptasia.... what I learned - get it early