Zoanthids stopped opening? (pics included)


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These guys have been in my tank for almost 2 months. They have not only seemed healthy, but they have multiplied like crazy (they grew about 15 polyps onto the rock next to them).

All of a sudden now they aren't opening up. I can't see any parasites on them and pretty much everything else in the tank seems content.

About 2 weeks ago I did add a new zoa colony that has a few bad polyps on it (I'll try to get some pics...I need a better lens) but if that's the problem I don't know why it would take over 2 weeks to surface.

This is what they looked like a couple days ago:


And this is what they have looked like since lights on yesterday morning:


I tested the water & everything looks OK:

Ammonia: 0
Nitrite: 0
Nitrate: 10
PH: 8.2
Salinity: 1.025
Temp: 78.3 (Temp fluctuates between 78.2-79.1 and back over a 24 hour period)

Any help would be much appreciated!


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<a href=showthread.php?s=&postid=12227693#post12227693 target=_blank>Originally posted</a> by davidandliz
do any of the stalks look bloated? specifically for the closed up zoos.

No, none of the stalks appear to be bloated.

I've seen zoas close up for various reasons over the years; dropped from the rock, something fell on them, new inhabitants too close or stinging, but nothing like that has happened here. They just stopped opening up.


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<a href=showthread.php?s=&postid=12228012#post12228012 target=_blank>Originally posted</a> by MUCHO REEF
Check out the link below


Thanks Mucho!

Here's hoping it's:

25. And the final reason may not be any of the reasons above. Why? Periodically, polyps will retract from days to 10 to 14 days, during which they will clean themselves externally. Then without any advanced notice, they will unfold like a flower or a summer’s morning.

I just got 2 new zoa frags via Fed-Ex today. My frag tank isn't up yet so I had no choice but to acclimate them & put them in the tank. Both frags are opening up after less than 30 minutes in the tank so hopefully the one pictured is just being temperamental.