Zooanthids refuse to open

ragc

AC Members
Dec 4, 2005
263
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Atlanta, GA
Is it normal for a zooanthid colony not to open at all one day? The other colony opened up today, but my growing 5 polyp colony has not. They look like they are going to, but then close up tightly again. :thud:

Recent changes have been the addition of one chunk of cured Fiji rock (not even close to this colony) and that of a saddle coral, which is on the same rock frag with the zooanthids that did open, so I doubt the saddle is secreting anything. I did re-arrange the rock slightly to accomodate the new rock, but the colony's rock was not moved. Current from my rotating powerhead is still the same.

I brought salinity down over several days because it was borderline high before at 32.25 PPT. Now it is at 30.5PPT. pH measured 8.0 this AM, down from 8.3, but with my 10 gallon these swings are within range (I added Kent buffer to elevate it). My Alk is high, my NO3 is <0.3 mg/L, NO4 reads "safe" on my in-tank tag, and PO4 is .5 mg/L. Temp is 78F.

I moved my xenia and colt away from the saddle anyway, just in case. Please let me know if this is normal behavior, or if it happens when changes occur like those described. These polyps have been very, very hardy up to now, and had been reproducing rapidly (I started with two) They were open yesterday with the rock and saddle there.

Thanks! :bowing:
 
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I'd give them a little more time before doing anything drastic.

Ideally your PO4 and NO3 shouldn't be detectable, but for the softies and GSP you have your parameters are OK. I'd try to get your PO4 down some more with some macroalgae perhaps.

I don't think 32.25 salinity is high at all. Unless I'm mistaken that's about 1.024 in SG? I've always run my reef at 1.025 SG as do many others. In fact a salinity of 30.5 (~1.0225 SG) is very low for a reef IMO.

Also, why do you consider your Alk "high"? Exactly how "high" is it? If you added the buffer too quickly that could affect the corals. You should also take care with the myriad of buffers out there. Some are phosphate-based which spell trouble in a reef tank. pH swings throughout the day in a reef tank are actually normal.

http://www.reefkeeping.com/issues/2004-09/rhf/index.php

As well, if the Alk gets too high it could affect your Ca levels, although with your inhabitants it's Ca levels shouldn't be a huge deal.
 
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They are fine today!
 
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