Entire zoa colony disappearing

[mlivvy]

I had an entire zoa colony just detach itself or close up and turn brown or wither away. Now the strange this is that its only happening to 1 particular colony and all other zoas are ok. The only other odd thing I noticed were strings (that look like coral mucus) were coming out from some of them. Any ideas? Parameters seem normal and I dont see any pests.

 

[VintageReefer]

Sounds like an infection. Have you tried dipping the colony? Did any survive?

 

[mlivvy]

Sounds like an infection. Have you tried dipping the colony? Did any survive?

I have a few colonies all on 1 rock. Should I dip the entire rock? Some do still open but it went down from 100s to maybe 10 that still open.

 

[VintageReefer]

I have a few colonies all on 1 rock. Should I dip the entire rock? Some do still open but it went down from 100s to maybe 10 that still open.

My guess is if it’s not external like pests, it’s bacterial

I would normally recommend lugols dip, but I’m not sure if the whole rock should be dipped. I would suggest we await folks more experienced with zoanthids

 

[Euphyllia97]

If you are sure it is not a pest, it is bacterial imo. Have you looked with a light into the tank at multiple moments during the night, making sure there really is no zoa eating nudibranch or eggs visible?

 

[crazyfishmom]

The strings of mucus makes me think you may have vermitid snails that started in that particular area. Can you inspect the area closely and see whether you can find hard tubes coming out of the zoa webs? I have a mini colony that I’m going to have to do this to because it hasn’t been opening like it used to and I inspected last night after lights out and saw the vermitids poking through.

 

[mlivvy]

The strings look more like tentacles. You can also see where they are detaching and trying to get away from whatever it is.

 

[mdpitts]

The strings look more like tentacles. You can also see where they are detaching and trying to get away from whatever it is.

That is downright creepy. My zoas haven't been doing well lately and on my little tank I witnessed an asterina eating a polyp and plucked that dude right off. On my bigger tank I think an urchin I got has been scraping his mouth over them. I'm so heartbroken when I lose a coral. I hope someone knows what those tentacles belong to.

 

[I never finish anythi]

Those tentacles look like bristle star arms to me

 

[I never finish anythi]

List tank parameters.

 

[mlivvy]

So after lots of tank watching I believe it was vermetid snails. I went to the LFS and bought a bunch of bumblebee snails. I noticed they quickly went to work on that particular rock.