What's wrong with my Zoas?

We purchased a small Zoa colony on 8/5/11. The first day we had it, we noticed an aiptasia in the middle of it. Per Coralline's advice, we mixed up some kalk paste and put it on the aiptasia a day or so later. The aiptasia died, and the zoa bounced back beautifully. The zoa was opening and closing and seemed happy for about a week. Here's what it looked like when we bought it.



After being out of town for a few days I came back to find all the polyps closed. My hubby said it had been closed while I was gone, about 5 days. We did a water test and everything looked good. After a closer look I could see what I was able to identify as hydroids on the zoa. There were quite a few of them, probably about 15 or so. I did an iodine dip and pulled as many hydroids off as I could with tweezers.

I've been to the lfs that sold it to me asking lots of questions. They have said that zoas are very resilient and to not worry about them as long as my water is all okay. On a side note, I've been using an API dKH test and was getting an 8 or a 9. My lfs tested the water and got a 5. They said that's why my zoas are unhappy. I bought a Sailifert test as it's supposed to be more accurate, and I got a 9.6!

Also, we have a trumpet coral that is thriving and growing, and a mushroom coral that is doing really well.

Here are my other parameters:

Temp = 78 - 80
pH = 8.4
Salinity = 1.025
Ammonia, Nitrite, Phosphate = 0
Nitrate = 10-15
Calcium = 440

We are doing weekly water changes, usually about 5-6 gallons.

Any help would be appreciated! I feel horrible that my zoa is not doing well. It appears to be melting.

 

I am not by any means an expert, but I would drop the temp to more the 76 range. I hear Zoas sometimes "cleanse" themselves and will be closed off for 7 days or more, maybe this is what is occuring?

 

If melting than I would dip it.

The usual suspects for dying or closed zoanthids.

Nudibranchs zoanthid eating.
Sundial snails.
Sea spiders.
Asterina starfish if found in the area or under the plug or frag.

Usually if it's a predator doing them harm they can be found at night on the frag or under it.

Good luck

 

Hi
Trust Your test kits for the Alk readings as in My experience there's no way your PH would be 8.4 with an alk reading of 5.
Work at getting that nitrate reading down some more its a bit high.
What lights are you using & how high are they in the tank?
Some Zoas like shady areas & little flow especially green ones.
Hopefully its not that brown jelly disease Corals - Bacterial

 

I've done several dips, iodine (Lugol's and freshwater), the only things that come off of it are little copepods. I've tried camping out looking for anything moving on it, and I don't see anything. How big are these predators?

We don't have a heater, so the tank tends to be about 5 degrees warmer than our house... I could try lowering the house temp a little if you think that will help. Thoughts?

 

We are using the stock PC lights that come with the Biocube. We had it on a rock shelf about 10-12 inches from the lights with a rock next to it that kind of shaded it a little. I moved it to the floor of the tank, about 16 inches from the light about 4 days ago, but there has been no change (except for it seems to keep deteriorating).

I just did a nitrate test and it seems to be at about 5-10 right now. It's really hard to tell the difference between dark yellow, yellow-orange, and orange-yellow!

When my lfs did the water test, they said my pH was at 8.1 with kH at 5. My at home test is a Tropic Marin and we consistently get 8.4 on it. We test weekly.

 

You should easily be able to see all of them with a flash light at night, sea spiders are a little harder to see and not that common.

Personally I am not concerned in that nitrate level in the least.

Not real sure where you are coming out alk wise but if pH is above 8.2 I imagine the alk could not be that out of wack.

Next time you dip use SW instead of FW. FW dips can really make them big time mad.

 

Oops! I did the FW out of desperation last week. I've been dipping it about once a week in SW with Lugol's. I let it sit in there for about 15 minutes.

I'm so ashamed to post this... here is a current photo of the zoas. I feel like I've let them down!

 

My green zoas looked just like that for a few weeks. There has been grassy algae growing in the middle, which I've pulled out with twizzers, then I've got some algae eaters (emerald crabs), moved the zoas closer to the light ( less than a foot away), moderate water flow and left them along (haven't touched for more than 3 weeks now) - all the "flowers" have opened up now and seem to be doing fine. I also feed mine rather frequently (shrimp and plankton). I'm not an expert at this at all, but since I was worried for a while and had the same answer from my lfs wanted to share the experience. Hope yours bounce back soon!

 

Thanks Anya. I hope I have the same experience with my poor zoas.