Help needed, Zoa's dying

[w_1qaz]

All my Zoas colonies have not opened for 2 weeks now. Some frags have melted completely.

Other corals in the tank are fine: paly, plate, candycane, mushroom, rics, duncan, ancan and Stylophora.

water parameters:
ph 8.3
alk 7.8
ntirate 1.0
ammonia 0
60 gal, over 1 year old.

I did a precautionary 18g water change a couple of days ago.

Any wisdom would be great.

 

[Spaceshrimp]

Are there any pest that you can see in tank or maybe livestock thats messing with them?

 

[DSC reef]

Zoas can be finicky and just up and melt, one of the most frustrating corals IMO. I could have colonies growing crazy while others are literally melting away. Check for pests including asterinas. I doubt it's chemistry as other corals are doing great and regular water changes will replenish things like iodine, etc.

 

[Double monti 61]

I have read about zoanthid eating nudibranch if you look closely you may be able to see them had some in my last system.

 

[Double monti 61]

Do not blame the poor little starfish

 

[DSC reef]

Do not blame the poor little starfish

Why, it's well documented that asterina does eat zoas and coral, not just by the many hobbyists who have also witnessed it including myself. Zoanthid eating nudibranchs is a possibility and also falls under the "pest" category.

 

[Dom]

Zoas can be finicky and just up and melt, one of the most frustrating corals IMO.

... and yet I find it to be just the opposite. My Zoas are at a point where they are taking over the tank, covering many pieces of my live rock. I'd almost consider them to be a pest. LOL

 

[DSC reef]

... and yet I find it to be just the opposite. My Zoas are at a point where they are taking over the tank, covering many pieces of my live rock. I'd almost consider them to be a pest. LOL

That's the thing, some color variants like rastas grew everywhere to the point of just giving frags away including red hornets. Blue hornets and some other color variants were just super picky and melt no matter what was tried, strange and frustrating to say the least, lol. In the end we just stopped buying certain morphs.

 

[Dom]

That's the thing, some color variants like rastas grew everywhere to the point of just giving frags away including red hornets. Blue hornets and some other color variants were just super picky and just melt, strange and frustrating to say the least, lol. In the end we just stopped buying certain morphs.

Well... I have all green Zoas. if you know anyone who wants a chunk of live rock with some zoa on it, let me know.

Today during my water change, I noticed I had a small patch starting in the substrate!

 

[w_1qaz]

I have not seen any livestock messing with them. I did have a blenny that liked to nip at my Stylophora but he has sinced been rehomed to my toadstool tank.

I have a few Astria's, but I remove them when ever i see them in the tank.

No pest i can see with the naked eye. The zoas are at multi-levels in the tank. Could nudibranchs be that prevalent to irritate that many separate zoa colonies?
The 2 largest colonies affected are over 100 polyps each.

I guess I could dip them, I have CoralRx on hand. I assume that would kill nudis if they were there.

Should I set up my spare 10gal tank and remove all of them?

This a very frustrating.

 

[mfollen]

Guaranteed no pests? Any pictures of recently affected zoas? Phosphate?

 

[w_1qaz]

Update: I did lose 50% of my Zoas. The rest started to reopen again.

They only thing I could really attribute to the issue was that I started dosing ALK/CAL in the tank.
Many be it was too much to soon combo.
Very strange that all the other corals in the tank were just fine (SPS and LPS), just the Zoa's had the issue.
Oh well, chalk it up to the hobby!!