Help with possible pests

greg1786 · Dec 18, 2023

Hi everyone. I have 3 small zoa frags. Two of them have recently have been showing irritation to something. One colony has closed up completely and will not open. The other has been opening sporadically from day to day. I suspected possible zoa pox, so about a week ago I removed them from the tank, "scraped" them using the edge of sharp tweezers under a magnifying glass, and then dipped them in coral RX. This seemed to help marginally for a day or two. I have another frag, less than 6 inches from the two afflicted frags, that seems completely unaffected. I snagged this photo just now, unfortunately under heavy blues as the lights are about to go out. Hopefully someone can look at this and shed some light for me. I will try to get a photo in daylight tomorrow. Thanks in advance for any help.

greg1786 · Dec 20, 2023

Any thoughts??

noobreefer2 · Dec 20, 2023

following

JayM · Dec 20, 2023

I bought a Rasta zoa frag with about 5 polyps on it months ago. Looked great for a couple of days, then closed up for seemingly no reason. Just as I was about to give up and remove it from the display (a little over a month), I saw some signs of life so I left it alone. Days later it was fully open and happy. It's been 2 months or so since then, and now has grown 6-7 more polyps.

If your parameters are ok and stable, just be patient.

greg1786 · Dec 20, 2023

JayM said:
I bought a Rasta zoa frag with about 5 polyps on it months ago. Looked great for a couple of days, then closed up for seemingly no reason. Just as I was about to give up and remove it from the display (a little over a month), I saw some signs of life so I left it alone. Days later it was fully open and happy. It's been 2 months or so since then, and now has grown 6-7 more polyps.

If your parameters are ok and stable, just be patient.

Appreciate the insight. The difference here is that these frags have been in the system for about 6 months. These rastas came in as two heads months and months ago. Did great, along with another frag(unknown zoa), grew a bunch more heads to what you see now in the photo. This issue just sprouted up recently, about 2-3 weeks ago. The system is 5 years old, params are rock solid, I am very diligent in water changes and keeping my dosers calibrated etc. I have a mixed reef with thriving sps and a few lps. The only thing in the tank affected are these zoa frags.

EricR · Dec 20, 2023

Did you find anything concerning when you scraped/dipped them?
Picture is pretty blurry but looks like a fair amount of gunk on the stalks.
I also see a "tube" structure sticking up in the middle but not very clearly -- is that a vermetid or strand of algae or?

Beyond that, I can't help -- zoas did great in my tank for about a year but all went into unhappy mode for many (many many many) months now and I kind of gave up on trying stuff.

greg1786 · Dec 20, 2023

EricR said:
Did you find anything concerning when you scraped/dipped them?
Picture is pretty blurry but looks like a fair amount of gunk on the stalks.
I also see a "tube" structure sticking up in the middle but not very clearly -- is that a vermetid or strand of algae or?

Beyond that, I can't help -- zoas did great in my tank for about a year but all went into unhappy mode for many (many many many) months now and I kind of gave up on trying stuff.

I did not see anything after the dip that concerned me. I honestly was hopeful that I'd find zoa spiders or sundial snails or basically anything that would make me go "aha!!" . Something I could realize and follow up with appropriate eradication. I just got home and snagged some daylight photos that are also hopefully more clear . I think the green tube like object you are seeing is just a strand of chaeto that has made a temporary home in the frag.