What could be wrong with my zoas?

I have about 5 zoa frags.

One I have had for about 6 months and it has grown from 7 polyps to about 15.

One I just got at a little Saturday convention thing our reef club had in april.

Two I traded for about a month ago.

And one was fragged for me at the last PARC (my reef club)regular meeting.

Now, 2 frags are perfectly fine.

But 3 frags are not opening properly.

The one I have had for 6 months, won't open at all. It has been about 2 weeks. The other 2 are not fully opening and seem to be getting worse.

Temp 79-80 F
Ammonia - 0
Nitrite - 0
Nitrate - 5
pH - 8.1
Alk / CA I am having difficulty stabilizing.

Alk ranges as low as 6 and as high as 11 dKH
CA ranges from 250 - 350

I have tried moving them to lower light (not right under the 175 W halide)

I have excellent random flow ( 2 Tunze turbelles w/ multicontroller) in a 58 gallon.

I also have (and all are doing extremely well) a caulastrea, 2 frogspawn, 1 monti cap, 1 porites, xenia, anthelia, green kenya tree, sinularia, and a clam.

I have seen no sweepers on my frogspawn, and the zoas are sheltered by rocks anyway.

Any suggestions?

 

That is strange. Frogspawn and Xenia are usually the guys that take a nosedive if water conditions are less than ideal.

Have you looked closely for snails or small nudibranchs/slugs around them? There are some that prey on zoas. It's also possible that they've picked up some kind of bacterial or fungal infection (though I haven't heard of this with zoas). If you want to be proactive, you could give them a dip in something like Seachem Reef Dip.

I wouldn't worry about moving them to less light. I have lots of zoas right under my 250w MH. They love the light.

Calcium shouldn't directly effect them, but the fact that your Alk is all over the place might be a clue. It's a sure sign that something in your tank isn't right. Have you tested your Magnesium? Too little mag will make it difficult to stabilize calcium and Alk, but again, it shouldn't directly affect the zoas.

 

ok, so did the zoos start closing randomly or was this after you fragged them? imo the pH is a bit low...but im not sure how sensitave they r to that...besaides that, have u recently changed ur bulbs or anything...heck has anything in ur tank changed?

 

Birdlady:

I have the same things going on with mine too. Some of them look like they have stretched out and ar thin and look like their skin is dingy and tough. Mabey its a chemical warefair thing amongst the corals. I have been running carbon and Purigen in my tank. I think mabey my photo period may be too long. Sometimes I leave on the lights in the evening when I am home to enjoy the tank when I know they need to be off. Corals need down time just like we do.

Just a thought

Jay

ALK is comming into shape by the way...Thank You

 

BL:

Here is some karma for your sick polyps. Do check out this link and the other links on the page. I will keep reading and if I find some magic zoagra I will share.

http://www.wetwebmedia.com/zoanthidbehfaqs.htm

Jay