Zoas won't fully open

[rovster]

Hi all. I'm new to the hobby and had a question regarding a colony of Zoas I have. Just to give a little background, I've been researching SW on and off for a year and took over an established BC14 a few months ago. The tank had been up and running for a year prior. It had some problems but I'm still working on it. Since I got it, I've upgraded the filtration with a media rack (CP, Pirg, FF), ditched the bioballs, and upgraded the return for more flow. I also bought new bulbs for the stock unit (never had been changed).

Anyway, everything in the tank has been doing well since I got it. I have some Palys, a small BSP colony, a hollywood stunner chalice, and 2 zoa colonies. The Palys, HSC and BSP are doing great. 1 Zoa colony has been growing and multiplying and has opened up a LOT since I got the tank. THe other colony is the reason for the post. The other colony was closed off for several weeks when I got the tank. I assumed they were dead. Over the last couple of months, they have started to open, but not a whole lot. THe rock they are on is completely covered with coraline, almost to the point that the zoas themselves look to be covered in coraline. They look different than the others. The colony that's doing well is in the middle of the tank, while the one that's not is at the top of the tank. I thought that might be the problem, so I moved them lower for a few days and no difference. I moved them back up because the rock they are on interlocks wiht another and adds a lot to the scape. I have noticed that in the last month they are starting to open up more. Most of the polyps are open, but I would say they are only 10-40% open when compared to the other colony.

I do a WC once a week, and check params a few days after. Am, Nirti, Nitra are all 0. Phosphate is between 0 and the next tier up, but closer to 0. Ca is 380-400 and kH is WNL. PH is in the 8.2 range and temps range from 79.x-82.x (working on that now).

Here is a pic of where we started...

Here is where we are now...
This is as big as they've opened...

Here's the other colony. Sorry about the washed out pic...the hermits occasionally bulldoze through this colony....

What do you guys think. Thanks in advance for any feedback!

 

[caudill187]

Hard to say. Are they getting enough flow? Too much light? Zoas like kH 9 or below, in my experience. I do not see any pests on them, but its hard to tell from a photograph. Try a 5 minute dip in Revive or Coral Rx (if you can get the rock in a seperate container) and see if anything comes off.

 

[rovster]

Thanks for the reply. I didn't think it was a water quality issue because the other colony of zoas is thriving, and its only 3 to 4 inches away from this one. I may try that dip, but not sure what that will accomplish. I'm soon going to add another PH to the tank, but there is pretty good flow in there right now with the MJ900 and K240nano. I added a few specimens yesterday (GPP, Xenia, and Goni) and they are all flowing around pretty good. I always thought they were too close to the light, but under the stock BC14 PCs, I never thought they could produce too much light. Actually, since I replaced my bulbs, they have opened more, but still not open fully. Thanks again. Looking forward to more replies. This is a great site.

 

[caudill187]

The dip may accomplish these things:

1. Give the polyps a "boost" fighting off any superficial fungal, bacterial, or viral infection they may have. The products I mentioned are antiseptic, and are gentle on zoanthid tissue.

2. Kill and help to identify any larger pests (zoa spiders, nudibranchs) that may be irritating them

3. Dislodge any algaes or other symbionts that may be growing on their surface. It looks like there may be some present in the photographs.

This may or may not be helpful but I have turned the health of many colonies around this way, even saving some very rare stuff I think when it is all said and done sometimes I realize that I can't always know why a particular coral "doesn't like" my system. For example, there may be a particular environmental micronutrient that they were very dependent on in their prior system, that is lower in yours.....sometimes I just say "who knows". Zoanthids come from a very wide range of habitats.

 

[MUCHO REEF]

rovster, how are your polyps doing since your last post?

Take a look at the link below and see if anything rings a bell. I will be updating the 25 to 30 reasons this week.

http://www.reefcentral.com/forums/showthread.php?t=1154238&highlight=25+reason

The one thing I wouldn't do is continue to move them around, it will stunt growth, cause stress and possibly add to any retraction you are currently experiencing. Hope to hear back from you soon.


Mucho Reef