Zoas Disappearing?

[Ryan S]

I am not sure why, but over the past couple of years, almost all of my zoas have slowly closed up and melted away. I don't see anything eating them. My tank parameters are fine. I have plenty of SPS that are flourishing in the tank. Does anyone know what might cause zoas to disappear? I'd say I had 15 different zoas over the past couple of years, and now maybe 3 or 4 are left, but also closing up and going to disappear soon enough... Very frustrating. Maybe there is some chemical in the tank they don't like, or require, that I don't add for them? (Cal, Mag, Alk are all good...)?

[zygote2k]

chemical warfare between zoas and other corals could be the problem. some coral species aren't mixed in nature like they are in our tanks.

Edited January 2, 2010 by zygote2k

[Ryan S]

chemical warfare between zoas and other corals could be the problem. some coral species aren't mixed in nature like they are in our tanks.

 

I always assumed the warfare was a close contact sort of thing. Could it take place over a distance in the tank, through the water? If so, that might be it. I assumed most of us kept a mix of SPS and zoas in our tanks, is that not true? I will soon be SPS only, but not by choice I suppose. I wish I could keep zoas still...?

[zygote2k]

zoas and sps come from 2 completely different areas and maybe they'll thrive together at first, but once the water chemistry becomes more favorable to sps, the zoas will probably recede. it just takes a while before you notice it. like paul b said about observing the cycles over a long time period. you're witnessing coral succession just like algal succession.

[Coral Hind]

Can you post some pictures of the remaining zoas? What fish do you have?

[Ryan S]

Can you post some pictures of the remaining zoas? What fish do you have?

 

I can take some pics tonight. I have a Blue Hippo Tang, Yellow Tang, Green Mandarin, Bellus Angel, and Percula Clown. None of which I've ever seen pick at any corals or the zoas. I've also looked at the zoas up close to see if I could see any worms or anything eating them, but didn't see anything. Based on how very slow it's been taking place, as my sps have started to slowly grow more and more, I think it could very well be the SPS simply taking over the chemistry in the tank. I have 3 different paly's, and they're doing fine though, they have grown and spread quite a bit. I will take pics of the zoas tonight when I get home, then put them into our FOWLR tank for the time being before they all die and trade them away for sps or something.

[Jan]

I lost 3 very nice zoa colonies not too long ago. One week they were they and two weeks later they were gone. I searched and dipped and searched and nothing. They closed up, shrunk and that was that. They were gone. Some said it was chemical warfare but honestly I couldn't see how especially since I have so much circulation in the tank and I'm so on top of water changes and all. Other colonies were fine. Last week I found a sundial snail in my tank which in all likelyhood was the culprit. They prey on zoanthids and they blend right in. They're very difficult to find. I found it by chance when I placed a small rock into a holding bin. The snail crawled off of the rock and I could see it against the background. Keep looking.

 

I am not sure why, but over the past couple of years, almost all of my zoas have slowly closed up and melted away. I don't see anything eating them. My tank parameters are fine. I have plenty of SPS that are flourishing in the tank. Does anyone know what might cause zoas to disappear? I'd say I had 15 different zoas over the past couple of years, and now maybe 3 or 4 are left, but also closing up and going to disappear soon enough... Very frustrating. Maybe there is some chemical in the tank they don't like, or require, that I don't add for them? (Cal, Mag, Alk are all good...)?

[Ryan S]

I lost 3 very nice zoa colonies not too long ago. One week they were they and two weeks later they were gone. I searched and dipped and searched and nothing. They closed up, shrunk and that was that. They were gone. Some said it was chemical warfare but honestly I couldn't see how especially since I have so much circulation in the tank and I'm so on top of water changes and all. Other colonies were fine. Last week I found a sundial snail in my tank which in all likelyhood was the culprit. They prey on zoanthids and they blend right in. They're very difficult to find. I found it by chance when I placed a small rock into a holding bin. The snail crawled off of the rock and I could see it against the background. Keep looking.

 

Here's a video of the zoa situation in my tank:

 

http://www.youtube.com/watch?v=9zBNLrpGmq0

 

Jan, do you have a photo of what that snail looks like? I have seen some flat looking snails in my tank, without shells, but they've always been on the glass, I've never seen them on the actual zoas?

[Jan]

That's what my zoa looked like.

Look for these but let me tell you that I couldn't find them when I looked for them.

http://images.google.com/imgres?imgurl=htt...sa%3DN%26um%3D1

I forgot the name of those snails that look like they don't have a shell. They also drop their foot as a defense. They're very good for your tank. I have loads of them. Just forgot their name...

 

Here's a video of the zoa situation in my tank:

 

http://www.youtube.com/watch?v=9zBNLrpGmq0

 

Jan, do you have a photo of what that snail looks like? I have seen some flat looking snails in my tank, without shells, but they've always been on the glass, I've never seen them on the actual zoas?

Edited January 3, 2010 by Jan

[Jan]

Stomatella is the name of the snail you may see on your glass at night. Some even say they eat cyano .

Here's a video of the zoa situation in my tank:

 

http://www.youtube.com/watch?v=9zBNLrpGmq0

 

Jan, do you have a photo of what that snail looks like? I have seen some flat looking snails in my tank, without shells, but they've always been on the glass, I've never seen them on the actual zoas?

Edited January 3, 2010 by Jan

[lhcorals]

I dont know if i would say warfare first. I have SPS and Zoo's in the tank and both are thriving. It has been a couple years now. Like Jan said i would keep an eye out for some kind of unwanted pest. A lot of these guys are hard to see so you will have to really observe closely.

[zygote2k]

After watching your video, I realized that you don't have a preponderance of SPS, but rather a mixed reef dominated by Palythoas. Maybe you have a predator like a sundial snail or maybe it still is chemical warfare but from the palys instead. Have you dissected a colony of zoas to see if there are predators?

[Ryan S]

After watching your video, I realized that you don't have a preponderance of SPS, but rather a mixed reef dominated by Palythoas. Maybe you have a predator like a sundial snail or maybe it still is chemical warfare but from the palys instead. Have you dissected a colony of zoas to see if there are predators?

 

I would remove all paly's if I could keep zoas. Those brownish paly's by the large sps piece have spread like mad, and those green ones that are curled on the edges, I'd remove them all if it might help. I can tell you that those green ones won't always curled like that on the edges, just maybe the last 6 months or so?

 

I haven't dissected a colony of zoas, but I would. I wouldn't know how to/what to look for though. Just cut them up and see if I can see any worms or anything?

[Ryan S]

After watching your video, I realized that you don't have a preponderance of SPS, but rather a mixed reef dominated by Palythoas. Maybe you have a predator like a sundial snail or maybe it still is chemical warfare but from the palys instead. Have you dissected a colony of zoas to see if there are predators?

 

I would remove all paly's if I could keep zoas. Those brownish paly's by the large sps piece have spread like mad, and those green ones that are curled on the edges, I'd remove them all if it might help. I can tell you that those green ones won't always curled like that on the edges, just maybe the last 6 months or so?

 

I haven't dissected a colony of zoas, but I would. I wouldn't know how to/what to look for though. Just cut them up and see if I can see any worms or anything?

[Sikryd]

What is your alkalinity and other tank parameters? Specifically alkalinity.

 

The general look of all of your paly/zoa's is that they lack fully skirts, or skirts at all. My first guess would be alkalinity is low, ie. below 8 and I have issues with mine.

 

I would also look at adding iodine, which may also be low due to the load caused by the amount of polyps you have.

 

(no PHornets in there btw ) Nice video - it helps to see everything and what they look like.

 

There is also sea spiders that can do this as well. I would watch the tank at night (generally only when they come out) with a blue or red led flashlight (or regular flashlight) to see if you can see anything walking around on them at night.

 

No chem warfare. I have a full mixed reef off everything you can imagine, some right next to each other with no issues. Thats just my experience.

[Ryan S]

What is your alkalinity and other tank parameters? Specifically alkalinity.

 

The general look of all of your paly/zoa's is that they lack fully skirts, or skirts at all. My first guess would be alkalinity is low, ie. below 8 and I have issues with mine.

 

I would also look at adding iodine, which may also be low due to the load caused by the amount of polyps you have.

 

(no PHornets in there btw ) Nice video - it helps to see everything and what they look like.

 

There is also sea spiders that can do this as well. I would watch the tank at night (generally only when they come out) with a blue or red led flashlight (or regular flashlight) to see if you can see anything walking around on them at night.

 

No chem warfare. I have a full mixed reef off everything you can imagine, some right next to each other with no issues. Thats just my experience.

 

My Alk is around 8. I just started increasing the Alk daily dose to get it up again. It was 10 6 months ago, been slowly going down as my SPS started to grow is what I figured? Iodine is something I don't add yet, but was wondering if it will help. I will get some. And those zoas are def. not purple hornets , but sort of similar. I can't remember the name of any of them anymore. So many names for the darn things. I will look for spiders at night. There must be something doing it. I want to cut one of the zoas open and see if I can see anything inside too. Thank you all for your help. It's very appreciated.

[lanman]

I would remove all paly's if I could keep zoas. Those brownish paly's by the large sps piece have spread like mad, and those green ones that are curled on the edges, I'd remove them all if it might help. I can tell you that those green ones won't always curled like that on the edges, just maybe the last 6 months or so?

 

I haven't dissected a colony of zoas, but I would. I wouldn't know how to/what to look for though. Just cut them up and see if I can see any worms or anything?

 

WARNING, Will Robinson, WARNING!! Those 'brownish paly's that spread like mad' sound just like the really dangerous ones to mess with. I have been clearing them out of my tank - but I wear a mask, gloves, goggles, and use tools at arms length to chip the rock out from under them.

 

bob

[Ryan S]

WARNING, Will Robinson, WARNING!! Those 'brownish paly's that spread like mad' sound just like the really dangerous ones to mess with. I have been clearing them out of my tank - but I wear a mask, gloves, goggles, and use tools at arms length to chip the rock out from under them.

 

bob

 

Bob can you go to 1:27-1:37 in this video:

 

http://www.youtube.com/watch?v=9zBNLrpGmq0

 

Do they look like the dangerous ones?

 

At 1:37-1:45 you'll notice the green paly's next to them have no skirts showing at all. Makes me thing the brownish ones could totally be the cause of that? I think the green ones used to have skirts until I moved them next to the brown ones... Removing all of those brown ones is really going to suck... There are a TON of them.

[lanman]

I have found that some zoa's are very sensitive to flow, some to light. Too high flow, they don't grow, too low and they can actually just 'drop polyps'. Other light/flow situations can cause them to 'brown out' - just close up, get kind of brownish, and fade away slowly. We have some people in this club that seem to have excellent results with zoa's. I'd love to hear from some of them as to whether or not they have to move their zoa colonies around to find a 'sweet spot' - or if they just never have any problems at all. I had 2-3 polyps of 'Darth Maul' that died on me within weeks of getting them. Right next to them a very similar paly (nightmare?) grew from 2 polyps to 15 polyps, and then started dropping polyps. I moved it with about 5 polyps left - now it has 4 polyps, but they are larger than before, healthy looking, and starting to grow again. I hate zoa's...

 

bob

[lanman]

Bob can you go to 1:27-1:37 in this video:

 

http://www.youtube.com/watch?v=9zBNLrpGmq0

 

Do they look like the dangerous ones?

 

At 1:37-1:45 you'll notice the green paly's next to them have no skirts showing at all. Makes me thing the brownish ones could totally be the cause of that? I think the green ones used to have skirts until I moved them next to the brown ones... Removing all of those brown ones is really going to suck... There are a TON of them.

Not identical - but very similar. They won't cause trouble if you leave them alone - but they will just slowly grow over almost every thing else (frogspawn seems to do them in, and some encrusting corals push them slowly back). I have a rock that is half covered with those, and half covered with green fuzzy mushrooms. They are a good match for one another - I can't tell if one is going to beat out the other or not. If I can get that rock out of the tank - I'll destroy the paly's. Mine are the exact same ones that almost killed Steve. I know, because I got the rock from him, and they were hidden in cracks and crevices, and grew out from there. I would get rid of them if possible, simply because they try to 'take over' everything else, and are pretty successful. I don't know about the green ones - I don't have those.

 

bob

[bluefunelement]

I'd recommend raising the ALK back to 9+ and keeping it steady - I suspect low ALK has weakened a few of my paly's recently since nothing else changed.

 

Also come out at night and see what's chomping on them - you might very well have some HH going to town on them overnight - my amphipods turned into a plague then turned on my zoas.

[zygote2k]

I would remove all paly's if I could keep zoas. Those brownish paly's by the large sps piece have spread like mad, and those green ones that are curled on the edges, I'd remove them all if it might help. I can tell you that those green ones won't always curled like that on the edges, just maybe the last 6 months or so?

 

I haven't dissected a colony of zoas, but I would. I wouldn't know how to/what to look for though. Just cut them up and see if I can see any worms or anything?

 

Take one of the dying colonies out at night and examine it closely with a magnifying glass and tweezers. Look for sundials, sea spiders, or anything that doesn't look like a zoanthid. You won't need to harm the zoas to do this. Go through all the loose colonies and check. If you don't find anything, then it could be a water chemistry issue, light and flow issue, or chemical issue. Rule out the easy ones first, then take measures afterwards.

All palys and zoas have palytoxin so don't get scared because you have some of the Outlaw Stew Palys.

[Jan]

Here's a pic to give you an idea of what to look for when looking for zoa eating spiders. Nasty little buggers blend right in.

 

Also check out WWM on zoanthid pests. Bob Fenner is amazing! I don't know why these things aren't put in the newbie section or somewhere as a sticky. They are so beneficial to the club and the same quations come up over and over again.

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

 

Edited January 3, 2010 by Jan

[GaryL]

Here's a pic to give you an idea of what to look for when looking for zoa eating spiders. Nasty little buggers blend right in.

 

 

looks like the the thing fro alien that jumps on your face when you get too close to it.

[Ryan S]

Here's a pic to give you an idea of what to look for when looking for zoa eating spiders. Nasty little buggers blend right in.

 

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

 

 

it's official. i have these spiders. lights were out, shined a flashlight in the tank, and saw several of them, some on the zoas, some on other things in the tank. now how do i get rid of them???