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FAQs about Zoanthid Health, Pests, Predators 7

FAQs on Zoanthid Disease: Zoanthid Health, Pests, Predator 1, Zoanthid Health, Pests Predators 2, Zoanthid Health, Pests, Predators 3, Zoanthid Hlth., Pests, Pred.s 4, Zoanthid Hlth., Pests, Pred.s 5, Zoanthid Hlth., Pests, Pred.s 6,
FAQs on Zoanthid Disease by Category: DiagnosisEnvironmental,
(Pollution/Poisoning, Lighting...), Nutritional, Social (Allelopathy), Trauma, Pathogenic (Infectious, Parasitic, Viral) Predatory/Pest, Treatments 
& Zoanthid Reproduction/Propagation,

Related Articles: Zoanthids, Sea Mat: An Ocean Of Color For The Aquarium by Blane Perun,

Related FAQs: Zoanthids, Zoanthids 2Zoanthids 3Zoanthid ID, Zoanthid Behavior, Zoanthid Compatibility, Zoanthid Selection, Zoanthid System, Zoanthid Lighting, Zoanthid Feeding, Zoanthid Reproduction

Ongoing Palythoa problems       12/10/19
Good morning crew,
<Good morning Nicole>
I have been scouring your site and I am sure my answer is there somewhere but I just can't seem to find it.
To keep a long story short every few weeks for many years I will lose a small patch (20-25 heads of thousands) of Palys to this brown jelly type stuff.
<These appear to be some type of sponge >
It will go away for a bit and then rear it's ugly head up again.
I am wondering if there is any one specific thing that causes this condition, or could it be any number of factors and this is simply how Palys react to something they don't like.
Of course I am hoping you can tell me that only one thing could be causing this but I feel like most things in this hobby it won't be that simple.
Thank you in advance.
<Sponges live in almost all marine ecosystems, from the shallowest coral reefs to the deepest, coldest parts of the ocean so, it is very easy that they have adapted to your marine tank; they are filter feeders, not coral eaters, but looks that they are suffocating your Zoas. I suggest to manually remove them; if the rock (s) they are attached to, is (are) easy to take out of the tank, you can remove them with a pair of tweezers or applying hydrogen peroxide directly to the sponges.>
PS while I have your attention, any advice for getting a dart fish out of a deep narrow overflow chamber? ��
<This happens at times and the best solution is to drain the overflow section and try to introduce a narrow net attached to a pvc pipe or some other long object in order to reach and catch the fish in only a few centimeters of water, if access to the overflow is limited, you can try the same but with the net attached to a flexible pipe or hose. Hope this helps. Cheers. Wil.>

Re: Ongoing Palythoa problems       12/10/19
Thank you for the reply.
Yes I do know about the sponges, they don't really concern me.
I am referring to my Palys turning brown and gooey and disintegrating.
<Ahh, ok... I thought you said this happens when sponges are present.>
Maybe the photo isn't very clear. This has been going on long before the sponges were present and often in colonies where there are no/very little sponges.
Any idea what is causing my Palys to turn brown and gooey?
<May have to do with water chemistry / quality>
It will only happen to a small patch at a time, go away, only to return again on a different patch of Palys.
I have attached 2 more photos that will hopefully show what is going on more clearly.
<Thanks, I can see what you mean more clearly on your excellent pix. Can you please tell me about your water levels (numbers)?>
Thanks again and wish me luck catching the dart fish! ��
<Good luck!... hopefully you take him out soon. Wil.>

Re: Ongoing Palythoa problems       12/10/19
Thanks again. The dart fish actually ended up being super easy to catch; for lack of anywhere to hide he swam straight into my net. Him and his 3 buddies were just added to the display tank yesterday.
<Ahh... good, perhaps you can block or limit the overflow slits a bit so that this won’t happen again, slender fish like your dart fish can easily pass through them.>
So back to the Paly problem, I have only recently started testing/dosing after 6 years in the hobby and have attached photos of my logs.
<Okay, let’s see>
My salinity is always at 1.026. I really don't see it being parameters though as this has been going on forever and only seems to affect a very small portion of Palys at a time.
<I don’t see readings re HPO4 and Nitrate... do you dose iodine?>
I know I have some allelopathy issues in the tank due to an unusual mix of corals I introduced before I knew what allelopathy was, so this is my suspicion.
<You may be right here>
I still find it odd that it only affects tiny patches of Palys at a time though.
<Is there any other Cnidarian life in the tank? Maybe nearby the Palythoa colony?>
I was just hoping maybe there was only one possible cause for Palys turning brown and gooey but I guess that is not the case.
Thanks again for your help
<Welcome. Wil.>
Re: Ongoing Palythoa problems       12/10/19

He jumped over the overflow, no way he would fit through the slits. Luckily the tank itself is pretty well covered.
I don't have a phosphate test kit yet, I started testing nitrates in the last few days, you will notice nitrite/nitrate readings on the last few logs on the far right.
<You're right, I missed this.>
Nitrites are always 0, nitrates have been hovering around 5-10ppm although I am not a big fan of my seachem test kit (hard to read)
and plan to get a new brand soon. All other tests are Salifert.
<I use Salifert mostly... a very reliable, easy to read test kit brand.>
I do not dose iodine, I will look into this.
<Iodine is required by most corals but should be dose with caution.>
As I said I am very new to the whole testing/dosing thing, I have always relied on visual observation and frequent water changes in the past, have had a lot of luck both good and bad haha so have decided recently to step up my game and force myself to understand the chemistry behind my aquarium.
<Good decision>
There are lots of corals in the tank, many of which I know don't mix well.
Ricordea, green hairy mushrooms, a few leathers including Colts/devils hand/ pink cabbage, a hammer coral, many Rock flower anemones etc.
But honestly Palys are the most prevalent thing in the tank, mostly due to a very invasive pale bluish green type that is sometimes the kind melting, sometimes not. I have added some activated carbon recently and plan to add more soon,
<Don't forget to suspend activated carbon use when dosing>
but I also know I need to rethink some of my coral selection but I'm not totally sure which to keep and which to move yet!
By the way I don't think I mentioned, this is a heavily stocked 150 gallon tank with a 30 or 40 gallon sump. It started as a 75 gallon 6 years ago and I upgraded to 150 about a year ago.
<Do bear in mind that corals need enough space to open freely without touching the other corals. Cheers. Wil.>

Identifying a possible plague     8/11/19
Hi Bob,
How are you? I hope you are doing great. Can you help me to identify something?
The picture is from a User that doesn't speak English.
Thank you very much.
Best Regards, Raul
<Hey Raul. These oblong pellets look to be fecal material... could be gastropod eggs. I'd vacuum out.
Cheers, Bob Fenner>

Re: Identifying a possible plague     8/11/19
Thank you Bob,
Do you think snails can damage zoanthids?
<Oh yes; some snail species predate Zoas>
Because that is what my friend is looking to solve. His zoanthids are disappearing.
2 questions:1. If we want our logo (triton) in the top of your web page what are the options?
<Oh, easy to answer. All sponsors on WWM receive equal random showing at the top, banner and bottom spaces for their linked logo pix. The cost is $300 per month for universal placement; which because Triton makes, sells products for all types of systems would be best: http://wetwebmedia.com/WWMAdminSubWebIndex/wwmsponsors.htm>
2. Can you also identify the attached things in the rock in the attached picture?
<Yes; pretty confident that these are gastropod (snail) eggs. Bob Fenner>
Thank you.
Best Regards,
Raul Labastida
Triton Distribución Latinoamérica

Re: Identifying a possible plague     8/11/19
Thank you Bob
Raul Labastida
Triton Distribución Latinoamérica
<Glad to help Raul. Cheers, BobF>

Weird Zoa Behaviour
Hello WWM !
<Hey Francesco!>
Is very long time that i read your website, i mostly often found either what i was searching, either something that was very interesting and useful for my hobbyist knowledge.
This time i need advise...
I am Francesco, proud owner of a pico and a nano, 10 years experienced reefer that just since last September re-started some reefing after a life-changing event (no details needed here :) )
So, on September 2018 i re-started with a 8gal (im a metric man, however i think for the site reference is better to use imperial qtys) Fluval shrimp tank 12"x12"x12", converted... i was eager to re-start, but i had not enough space available for something bigger and however i considered my knowledge and past experience enough to start consciously a nano/pico ( a very small one let's say...)
The tank was setup with a Kessil A80, A Sera PS130 Skimmer (oh the little jewel...) and a HOB filter loaded with ceramics bio media, and a Tunze Turbelle 6040 with controller (oh the beast !)
Inside is now left a 7.7 lb of LR, after an excessive initial load (22lb) that was strongly limiting the water circulation.
Over the months (and especially in February) the system was "converted" with an external "reactor" Sera Prefix, moved by a Newa 1.200 (317 gph :D )
which returns with several spray bars in the cube, creating a soft but consistent multi flow.
Daily, a Jebao OW-10 (oh the little funny thing) kicks 4 times x 30min just to move a bit the water in a chaotic way.
Parameters :
KH : 11.0 - 11.5
CA : 430 - 450
MG : 1350 - 1380
PH : i do not remember last time i checked...
Temp: 24-25
Sal : 1025
Life Stock is
Lysmata Amboinensis ,1 Debelius, 1 Little Ocellaris, 1 Clibanarius tric. Several Zoanthus colonies (4 kinds), 1 hitchhiker green neon Paly, 1 yellow Parazoanthus, a hitchhiker Discosoma (i would say a neglectus ...), Pachyclavularia, a hitchhiker Gorgonia (no photosyn) and a Stylophora bicolor.
Everything is thriving (NO3 1-2 ppm, PO4 0.1 ppm), spreading, coloring, reacting, multiplying... the Gorgonia is now branching from the original little single branch (which i consider a personal success... for the moment...)
All but a little colony of Zoanthus (the last i have put into)
<This is likely an important fact>

that in the last 2 months reduced from 6/7 polyps to 2.
The colony was (and still is) on the frag plate, and was quite arrogantly (from me) positioned in the middle of another giant spreading Zoanthus colony (with some space ... 1" around).
<Mmm; not enough: Insufficient for chemical allelopathy>
While aware that could have been some "chem war", i witnessed many times a self assessment of the fighting parties (mostly softies) and also consider it a necessity for the creation of the coral palette on the LR, so i decided to put them there and observe.
The polyps started to die, one by one, showing the distress signs (irritated polyp, closed mostly of the day or just half opened for few very minutes) one by one, never together.
This behaviour, follow by the progressive shrinking and detachment of the polyp, led me to the conclusion that the disease was parasitic.
<? Really? Did you observe actual parasites?>
I continued so to observe the sick polyps trying to catch snails, Nudis, spiders, eggs, holes, excrements and whatever else anomalous, day and night... but nothing.
Just once i removed an Asterina that was clearly eating one polyp, but i always had the suspicion that was an opportunistic behaviour from the star and not a predatory one.
However the star was removed.
The polyps continued to recede and die.
Two weeks ago i so decided to move the Zoas, and being the "little" tank quite overcrowded, i moved them to the "big".
Very fast : the "big" is a 20 gal tank with 3 movement pumps and a return (200gph) granting a very good diverse flow, has some kind of sump system (my project, quite long to explain, but the functionality is a sump functionality), Sera PS 130 Skimmer (oh i damn love Sera skimmers...) and the parameters are a mirror of the "little".
The tank is equipped with a Kessil 360 which runs at 80% peak (30% blue) 10hrs/dd.
The "big" has started on 07 December 2018, is a quite younger tank but however had a good cycle and just recently got the first load of softies (1 Ric, 1 Rhoda, 2 Discosoma, 3 Zoanthus, 1 Clavularia) all of them "ultra" (as i would like to have finest specimen there, only) and has the classic (for me) Amboinensis + debelius set, and an Ecsenius bicolor that was called in for the algae/GHA initial war as well with 4 Clibanarius tric. and 3 Trochus.
I placed the "sick" Zoa in a very open place, with no neighbours, good light and good movement. Probably i placed them in the best spot of the tank that i was reserving for the (very) future SPS i wanted to try there... but hey... my Zoas are sick !
The behaviour of the sick polyp seemed initially to persevere, with a huge anxiety from my side due to the possibility of having introduced a parasite in the "big" (who is yelling since the start of my email "QUARANTINE TAAAAAAANK!!!!" ??? :D)... however is now a couple of days that the polyp
does not close anymore, however now both of them are stretching up with half closed mouth (also the mouth is stretching to the light), the foot has a length that i never seen in a Zoas... almost 1" ...
So... what is going on by your opinion ? I would exclude a light problem as mostly they now receive a bit more of light, PAR wise... water parameters are ok, and under direct feed (reef powder food from ocean nutrition 2xweek), they positively react...
I do not see an immediate threat and generally i never act on the rush if a catastrophe is not already ongoing, but i exhausted all my possible explanations and i do not feel comfortable so...
While waiting for your reply, and apologizing for the long (and still incomplete) email, i express my whole admiration for the WWM knowledge shared base, the crew and the thousands of times that directly or indirectly you provided help to some reefer pal in trouble...
Thanks and My Best Regards
<My best guess is that the continuing odd/stressful behavior was a continuation of the allelopathy from the smaller system. I would leave the one odd-acting Zoanthid colony where it is for now; and not worry re possible pathogen involvement. I might step up your dosing of iodide-ate here.
Please do write back in a few weeks time regarding your further observations. Bob Fenner>
Re: Weird Zoas Behaviour     3/12/19

Hi Bob and thanks for the super quick reply, will do as advised and let you know !
All the best !
<Thank you Francesco. BobF>

Zoanthids problem?     2/22/18
Hi Crew,
Some of my Palythoa have been closed up for a week or so now.
<Mmm; a bad sign; perhaps portending a bad time for all life here/// No data re system, water quality, other livestock, history....>
I have hundreds of different types. The Zoanthids seem fine but the large polyps (Palythoa I’m guessing) seem effected. This doesn’t look like zoapox to me although maybe it is the beginning stages?
<Summat is amiss here.... READ: http://www.wetwebmedia.com/zoanthidhlthfaqs.htm
and the linked files above. Bob Fenner>

Re: Zoanthids problem?     2/22/18
All other live stock looks great. Sps. Lps. Etc. water chemistry is good. Alk 7. Cal 400. Nitrate 0. Phos .05. Lighting Radions.
System is about 4 months old but water was moved from a 2 year old system.
<Ah, good>
I only use marine pure blocks, no live rock really accept what coral is attached. Oversized skimmer.
Hope that helps
<Yes; well, something is bugging this one colony. What is "next door" may be germinal. BobF>
Re: Zoanthids problem?

What do you mean it may be germinal? I have several colonies in this one system with this same issue.
<... please re/read on WWM re Zoa compatibility>
I’m trying to do some research...Could this be some type of hydroid?
<... yes. Do you see such nearby?>

Aiptasia Quarantine Time     6/14/17
Hi Guys,
I have display tank which contains a handful of coral specimens, mostly Zoanthids, but this tank also suffers from an Aiptasia infestation.
Infestation may be too strong a word, as they are well controlled with a combination of wand removal and peppermint shrimp. At some point I would like to remove and frag some of the coral for other tanks, but I fear
spreading the Aiptasia to another tank. I'm planning on a quarantine of the frags prior to introduction into another system. So my question is - how long would you maintain a frag in quarantine until you felt you could confidently declare if Aiptasia free?
<Likely a few weeks would "do it" for me... giving any transferred pest anemone bits to grow sufficient to be noted>
<Welcome. Bob Fenner>

Nudibranch id please       1/28/17
Hello there, I first want to thank you for previous help a long while ago.
My issue was dozens of hermits large and small disappearing completely, shell and all. You (can't remember which crew member in particular) had suggested it sounded like I could have a predacious worm. Soon after I managed to find 2 large fire worms when looking at night. I managed to remove the pair, and haven't lost a crab/snail/shrimp since!
But as for my current question. Yesterday I purchased some corals, specifically a colony of Ricordea yuma, a colony if Zoanthids and a colony of Palys. In addition to the wonderful turbo snail and emerald crab hitchhikers I scored, this morning to my surprise I have a tiny Nudibranch and a small starfish on my glass. The starfish is I believe an Asterina
(grey with 6 arms) but it's at least twice as big as any I've seen in my tank previously.
But my main concern for the moment is the Nudibranch. Of course I'm worried he could be the type that eats Zoanthids, although I'm hoping that the fact that I have found him in the glass is a good sign. Regardless, he is in jail for the moment. I should add that I have now inspected my new Zoas and don't see any eggs as of yet.
I would really like to keep this guy if I can, so please tell me if you think he is a good Nudi or a bad Nudi.
<Mmm; appears to be a Aeolid... do consume Cnidarians... often look a lot like their prey>

I hope these photos are clear enough to get a good identification. He is about a quarter inch long.
I would also like to know, if he does end up being a Zoanthid eating Nudibranch, is that what they eat exclusively?
<Don't know; but too likely so. See the Net w/ the family name...>

Rather than killing him I would like to set up a nano tank to keep him and any other future questionable hitchhikers but if he will die without Zoanthids I guess I have no choice.
Thanks in advance!
<Welcome. Bob Fenner>

What could this be?    8/4/16
Hi I found a few of these critters crawling on some Zoanthid frags. You can not see these with the naked eye. I found them with a jewelers loupe and then took these photos with my iPhone under a microscope. Hoping they are a detritivore but I am fearing the worst. Thanks in advance.
<Appear to be Mites/Acarinans... I wouldn't panic. Bob Fenner>


trying to id a hitchhiker on my Zoanthid coral     4/9/16
Hello Crew,
I'm trying to id a hitchhiker that came on my Zoanthid coral. it looks like it has tentacles and is very fast.
<A polyp...?>

it seems to cover my polyps with a tough fibrous film overnight
and also has built a den type cave with a very tough covering, some type of fibrous material and lots of very tiny white sea shells mixed in as well.
<Mmm; a Sedentariate Polychaete.... likely>
it's killing all my Zoanthids
<Unusual; what other life is here? Water quality measures? What changed recently?>

and I haven't been able to see any more of it than 4 small tan looking tentacles that come out and if it sees a shadow it darts back in the rock.
Any input I could get would be greatly appreciated, any questions you have for me I would be happy to answer best I can.
Thank you for your time
<Can you send along a well-resolved, cropped, few hundred Kbyte image? Bob Fenner>
re: trying to id a hitchhiker on my Zoanthid coral

I've been trying to get a pic of what we can see on occasion, but have been unsuccessful so far, if I can get one I'll email it right away
Thank you
<Real good. BobF>

Zoanthids looking crinkled???      2/6/15
Hi Bob and crew! Thanks again for reading. Your site and dedication are the best.
<Ah, welcome>
I started this colony with just three polyps 3 years ago in my 10 gallon nano tank.
<Very nice!>
When I set up my 225 gal a few years back I transferred them over and they exploded. There's are hundreds of polyps. They go through changes and phases from time to time but this crimped or crinkled aspect that some of the colony has is very odd.
<I see this... could be a few things going on here: Some sort of nutrient deprivation (do you have N, P, K?; What do you feed?), allelopathy (fighting amongst themselves, other Cnidarian life there), toxic reaction from... maybe the BGA in evidence here....>
This had been going on for two weeks. They all open up. The picture was taken after I fanned the rock so I was messing with them. Although they open the skirts look so odd. Strangely the skirts with a lot of green fluorescence seem to be the ones affected. I have scoured the site and I can't seem to find anything about this exact problem.
<Oh, the above rather common issues are covered>
Just people who's polyps won't open. I figure that it may be from allelopathy. Also, I don't have any nitrates right now. Water too clean? But no other of my other colonies are showing sins of distress at all nor are my corals. Let me know what this might be. It would be so sad to lose this gorgeous colony.
<Please have a (re) read here: http://www.wetwebmedia.com/ZoaDisDiagF.htm
and on to the linked files above in this series detailing Zoanthid Disease. Bob Fenner>

Re: Zoanthids looking crinkled???      2/7/16
Ok. Thank you Bob. In the picture what looks like BGA on my rocks is actually a dark red coralline algae.
<Really? Is it soft to touch? Slimy? Do you have a low power scope (with a USB connection!?) that you can take a look/see?>
I don't struggle with nuisance algae problems anymore (for now). I'm going to do some more reading on where you directed me. Thank you, Kinley
<And... we'll be chatting. BobF>
Re: Zoanthids looking crinkled???      2/7/16

Hi Bob. Thanks for taking an interest in this. I do not have a scope. Although, It used to be one of my favorite hobbies as a child.
I think I may have to invest in one.
<There are some FAB ones nowayears, so much tech. for such low prices. See Amazon.com alone>
Your reaction to my strange coralline algae is very similar to the reaction of my reef mentor. I had him come over and take a look at it 6 months ago due to some comments that people online made about it being Cyano. He's been in the business for 40 years. In fact he was the one that gave me your book. I live in the mountains of Oregon and I have absolutely no resources here other than him the internet and my books. He also thought it was Cyano until he touched it. it's very encrusted on to the rock and not slimy to the touch at all.
He agrees with me that it is in fact a rare type of coralline algae. I've gotten used to it over the years. It started in my 10 gallon nano tank, seeded from some live rock probably and I guess liked the conditions. In my 220 gallon it has covered everything. I would be very curious to hear your opinion. I have found a few others on line who have this too. luckily there's a lot of purple as well which does sort of balance out the visual aspect.
As far as my Zoanthids go, I believe you're theory that the nutrition is probably the problem. I have not fed the colony very much and now it's so large I'm sure it needs more. I also really don't have many nitrates or phosphates right now which is also why I don't have an algae problem.. ugh...its so hard to find the right balance.
<But so necessary>
I'm sending you a full tank shot so you can see how this weird type of coralline has spread all over.
<No pic attached>
<Cheers, BobF>

New to the Zoanthid Game... hlth., rdg.     6/14/14
Hello there! I just want to start out by saying this is the first place I go when I have a unique dilemma. Anyways, i started a 55 gal tank about 2 months ago. The inhabitants are a snowflake eel,
<Will need more room in time>
six red-legged hermit crabs
<... will be eaten by the Eel when they're changing shells>
and a turbo snail. Also, as far as Zoas go,
<Mmm; am hoping by your supplied title above that you fully realize how toxic Zoanthids can be... IF disturbed/challenged>
I have a colony of radioactive dragon eyes, 1p of pink and gold, 2p of orange bam bans and some other Zoa my friend sent me for free that I have yet to identify (All got next dayed from the same person). The dragon eye colony opened almost immediately after being put in my tank but the colors seem to be off. The orange bam bans also appear to be doing well. Their skirts are green but the center seems drab orange/brown rather than that bold neon color..? I’ve personally seen this colony in my friends tank and it was nothing short of vivid. however, he did have the blue LED’s pounding the color out of them :) The orange bam bans also appear to be doing well, yet they other two frags haven’t opened in 3 days/4nights. have all the frags on an egg crate shelf about 12” from my T5 light equipped with two true blue actinic lights and one 10k daylight. I run the lights about 10hrs a day. My water parameters are: pH- 8.1 NH3 and NH4- 0 NO3- 0 N04- About 20ppm
? Mmm... Do need some nitrate; and phosphate>
Alk- 2.0meq/L. Temp- 79. They were in a tank with ocean revive LEDs, which seem pretty powerful compared to my lighting. What I’m trying to get at is should I be worried that the other two frags not opening?
<In time; yes; cause to be worried. IF you have another system that is established... I would be moving them if not opening w/in a week>
They look just like the others when closed and appear to be alive. Should i try moving them farther down in my tank and see if they open where its darker, or just leave them alone?
<Not likely helpful in terms of physical environment and DO wash your hands carefully after placing them in the water, especially IF you touch these Cnidarians>
I also have two powerheads and sufficient water movement.
Thanks Again!
<Should I encourage your reviewing all we have archived on WWM re Zoas? Yes: http://wetwebmedia.com/CnidIndex2.htm

Right below Corallimorpharians. Bob Fenner>

Dark Red Encrusting Algae Killing Zoas... BGA       4/4/14
I have what I thought was dark red coralline growing in a lot of the rock in my tank.
<Mmm; likely BGA>
All colors of coralline seem to expand rapidly in my tank, so didn't think anything of this color.
<Does it feel slimy?>
However, over the last few days I've noticed that it's grown onto a few Zoa colonies and now they are not opening, so I'm a bit worried. It's the exact color of Cyano, but seems to be encrusting just like a coralline. It feels slightly slick to touch and is fairly difficult to scrape off, though with a fingernail I can scrape a bit unlike purple coralline which won't budge. It appears to be growing mostly in high light, high flow parts of my tank. Any ideas what this might be and how to combat it?
<As we've both stated>
tried a few days of lights out like I would with a Cyano outbreak, but no apparent effect. May try a peroxide dip or even Red Slime Remove next (though have had bad luck with it once before so hate to even consider it). Any advice is appreciated.
<Time to send you; have you read re Cyanobacteria and their control on WWM.
You know how to search, use the indices?
Bob Fenner>

re: Dark Red Encrusting Algae Killing Zoas       4/5/14
Appreciate the quick reply. I had discounted Cyano because this is so resistant to high flow and manual removal.
<Mmm; not all; by a long-shot>

I literally have to scrape it to remove it from rocks and it's growing in the highest flow areas of my tank. Are there growth forms/species that
don't follow the normal characteristics?
<See WWM or my Algae Control book (on Amazon) re. BobF>

Zoanthids behaving weirdly    1/20/14
Hello my name is Vinay I'm 13 and am looking to get into the hobby
<You're in!>
 I have had my tank for six months now and have be doing regular water changes and maintaining my tank well. The tank has been doing until the last few weeks my Zoanthids have been acting weird lately they all of a sudden started to shrivel and within days started to brown. And every thing else in the tanks is doing fine. I checked the perimeters and everything seemed to be fine no nitrites ,ammonia and phosphates the weird is that my Zoanthids are still multiplying the baby polyps comeback fine the brown any idea what it could be.
<... in a word: Allelopathy. Search this and Zoanthid Compatibility on WWM and read. Bob Fenner>

Button polyps acting funny..??    10/29/13
I have acquired two separate small pieces of live rock with button polyps growing on them. They were fine for about three months and now a few have opened up (all the way if you will) and wrapped down around themselves. I have tested my water 8.2 pH, the tank is cycled and i have 10ppm nitrates and am running a protein skimmer. They all eat (even the closed ones) when i feed them. Am dosing Fluval 3-Ion and running a protein skimmer.
They have been like this for going on 5 weeks. there are more pictures of them in my photobucket account.
<... what other Cnidarian life is in this system? Do you dose iodide-ate?
If so, what, how? The NO3 is fine; do you have measurable HPO4? Bob Fenner>

Re: Button polyps acting funny..??       10/29/13
2 small mushroom polyps and they are clear across the tank on a different pile of rocks. All my fish are being QT for marine Ich but that's been ongoing to 8 weeks now. So there is a cleaner shrimp, 3 hermit crabs, 3 turbo snails, 2 bumblebee snails and a Fromia starfish. And my phosphate are 0ppm.
<Ah yes; a problem. Search, read on WWM re the need for all chemo-photosynthates for some/measurable soluble phosphate. BobF>

Mushrooms and Zoanthids... allelopathy, starvation knocked on, reading and great self-discovery!   10/10/13
I have hard and soft coral systems that range from Acros to polyps and everything in between. My levels are acceptable if not near perfect for all of my tanks.

The tanks in question are a 75g drilled with 30 g sump. 80
watt led lighting, PhosGuard in a reactor,
<... you realize chemo- photo-synthetic life requires measurable soluble HPO4>

carbon in a bag a week out of the month, SeaChem matrix, refugium, two 750 gph powerheads, 1250 gph
Ammonia, nitrite, nitrate 0
<... sigh: and measurable NO3. Please read on WWM re>

 phosphate less than .25, alk11, ph 8.22
daytime, I feed a mix of flakes heavily, bribe
<Brine likely; Artemia>
 shrimp once a week, phyto once a week.
<See WWM re this as well. Of little use in most settings>

Dose AquaVitro ions, calcification, 8.4, fuel once a week to where Mag stays around 1300, calcium 420, iodine at .06, iron not registering with my red sea test kit, but fuel has iron, so not sure if the test does not pick up this particular type of iron or what. Potassium at 385. This tank houses only soft corals and a tube anemone
<Cerianthus? Not compatible... see WWM re this as well>

 along with fish and inverts. The problem I am having is with mushrooms melting, Ricordea shrinking and detaching, and Zoas melting away.
<... after you're done searching, reading, you'll understand why. How to put it/this: Your problems are obvious>

<Likely "Palys">
do great, leathers do great, polyps do great. Tank has been up for two years and this started with just the Zoas 3 months ago. More recently, I have a separate soft coral frag system, 200 g, 2200 gph pump, divided into 4 stair step tanks.
One section has mushrooms and leathers, one has polyps , other two house fish. My Ricordea are starting to shrivel and detach in this tank as well.
It has same readings and fixings except ph is 8.16 daytime, nitrates are at 5ppm, and the lighting is 120 watts led 24" off the tank over a 75g area.
Both systems have skimmers,
dsb, ample live rock.
<.... So... what are your choices? Provide or don't eliminate needed nutrients, and either remove the Ceriantharian, or the other mal-affected Cnidarian life. Keep reading. Bob Fenner>
re: Mushrooms and Zoanthids  10/10/13

What is WWM?
re: Mushrooms and Zoanthids... "I (don't) want to hold your ha ha ha ha ha hand!"   10/10/13

I see, wet web media, what should I read and which section can I find it in?
<... the indices; search tool... on all 12k some pages... the topics listed on your first query... B>
Re: Mushrooms and Zoanthids... comp. f's  10/12/13

So I read tons of post and answers on WWM. Thank you for the great knowledge base and for answering all these questions so there is such a vast reference to pull from. First I removed my tube anemone from my 75 and added carbon. I also added carbon to my 200 g frag system. Other than carbon and a water change, which is coming tomorrow, is there anything else
I can do to prevent this from happening again if and when it gets fixed?
<Mmm, yes; a few things. Principal amongst these is careful introduction of any new stinging-celled life... The SOP mentioned over and over to "mix water" back and forth from the isolation/quarantine with your display system you intend to move the animal/colony to>
Also are the Palytoxin from plays poisonous to the Zoanthids?
<Yes; some more so than others>
And why are they not affecting any polyps or leathers? Thx
<They are better competitors... less susceptible to Terpenoid warfare.

Zoa pest???    8/22/13
Dear Crew
Is the attached pic showing a horrible infestation of eggs of a Zoa predator??
<...  Looks to be an algae overgrowth>
The Zoa colony was hardly having a couple of polyps open but had a great color so took it.
The Zoa is in QT currently and will remain for few weeks.
If you feel this is indeed pest them I win return it to the LFS
Also, if this is indeed eggs, any cure? Any gestation period for the eggs?
<... You need to fix whatever is malaffecting the Zoanthids... Likely either some aspect/s of water quality or the proximity of a more powerfully allelopathogenic Cnidarian/s. Read here:
and the linked files above. Bob Fenner>

Re Zoa pest???    8/22/13
Dear Bob
I just got this specimen from the LFS and have not yet introduced to display.

This will be the second livestock with the other being a small Acropora.
So the stinging part is now not happening.
Just reset my tank due to Aiptasia.
So don't want to take any risks.
Have freshwater soaked and dried the rocks for 2 months on and off to ensure total dry rock.
Even doing QT for macro algae.
How do I ensure this is algae or whatever and treat it???
<Likely will just "go away" on its own... I would just quarantine the Zoanthid colony for a few weeks and move it w/ or w/o the algae>
Any resources in WWM??
<Not re this, no>
Should I observe behaviour for a few days to better identify the issue??
<A few weeks>
Btw, QT is just a 10 gallon acrylic long tank floated inside the main tank.
One small power head for flow.
<Then in here>
No filtration. Just daily water change of a litre approx from display.
<Mmm, I'd get/use a separate system then>
<And you, Bob Fenner>
Re: Zoa pest???    8/23/13

Hi Bob
Why did you mention the get a new QT?
<You really could use this separate system... for isolation, quarantine, treatment...>
The water will be changed manually from the display to the QT and from there thrown away.
>Once a day; without filtration? Not the route I would go. B<

Nudibranch ID    1/11/13
Can you ID the attached pic of a Nudibranch? I believe it is the type that eats Zoanthids, but I see no damage to any of my colonies and I found this guy in the sump. Thanks!
<Mmm, yes... appears to be an Aeolid... do place the string:
"Aeolid predators of Zoanthids"
in your search tool and read re. Bob Fenner>

cropped and enhanced
Re: Nudibranch ID    1/11/13
<Welcome Van. BobF>

Zoa hlth.    7/30/12
Hi guys!  I’ve been fortunate until now not to have to look anything up or ask any questions from you and your wonderful site!  I do have a problem now... I bought a rock with about 40 zoos on it.  They opened the first few days and then stayed closed.  I know... this happens but while they were closed, they started covering with (going to try to explain this as best as I can) a velvety dark green. 
<Not good>
They have since started to die.  I took them to a great saltwater warehouse (I know them) and asked them to look at it.  They weren’t sure what it was but told me to do a dip with my Kent Tech-D and gave me some Revive to help them along.  They still are closed... still some dying off.  Can you help me?  Thanks so much in advance!!
<There appears to be a bit of BGA near the colony... this could be a negative influence, but much more likely is some sort of allelopathy w/ other Cnidarians in residence. Read here: http://www.wetwebmedia.com/ZoCompF2.htm
and the Cnid. allelo piece you'll run into. Bob Fenner>


Unhappy Zoas 12/11/11
These were looking great for the first 2-3 weeks I had them, now they are
decidedly very unhappy. Let me start with my tank specs:
29g biocube
150 watt MH lighting, 7 hours per day
1.023 sg
<A little low>
8.1-8.3 ph
10-11 dKH alkalinity
0 phosphate/nitrate/nitrite/ammonia
<Boing! Need measurable HPO4 and NO3... this is at least one dire issue... starvation. Whatever you're doing to render these at zip needs to change.
See WWM re Zoanthid needs>
Two 425gph flow heads
Phosphate reactor w/maxi jet 1200
AquaC remora skimmer w/maxi jet 1200
I've measured and checked everything I can think of, Googled for solutions and pictures, without much luck.
What's going on with these guys, and can they be saved? Thanks in advance!
<Can. Bob Fenner>

Re: Unhappy Zoas, HPO4 12/11/11
I'm using a decent size phosphate reactor to get it down to zero.
<Can't live...>
It was at 0.5ppm previously, and have been told elsewhere that 0.01 ppm is a "high side limit" for phosphates.
<Mmm, not so>
I target feed every other day with zooplankton and the occasional frozen Mysis shrimp.
I found a lot of FAQs re: Zoas on the site, but did not find one called "Zoanthid needs". Would you mind terribly sending me a link?
<Read here: http://www.wetwebmedia.com/zoanthid.htm
The linked files above. B>

Zoa Pox and Weird Brown Algae Problems, Please Please HELP 9/29/11
<Hi Jamie>
I know you are swamped with emails and I hate feeling like I'm bugging you with mine but I need help bad. PLEASE! I have two problems that I have no idea what the causes are. One is Zoa pox, the other is a stringy, hairy like dark brown "algae" that almost ALWAYS starts growing on and completely covers the sand during the day and creeps up everything else with it's fine hairs and grows there too. I don't think it's diatoms because I had that before when my systems were cycling and this seems very different. It comes out only when the main lights are on and mostly disappears when the lights go out, just to come back out the next day all over again.
<Mmm, actually sounds like Cyano to me, it does show it's ugly face in many colors. Take a look here. http://www.wetwebmedia.com/bluegralgae.htm>
Okay my specs and parameters are - 2 Biocube tanks (a 14 & a 29 halide)...both have the brown algae stuff and the Zoa pox. The 14 gallon has been up for 8 months and the 29 gallon has been up for 3 months.
Neither are linked together by anything nor am I swapping water, though I did in the beginning to get the 29 gallon started faster.
Both Biocubes have modified filter systems (I removed the tabs between chamber 1 & 2 for increased flow, chamber 1 on the 29 gallon has 75 watt heater, 14 gallon has Biocube protein skimmer; chamber 2 on the 14 gallon has filter floss on drip tray with Purigen, filter floss, and Chemi-Pure underneath, 29 gallon has half size drip tray with filter floss where the water comes in to catch debris and Hydor protein skimmer (which I'm having a hard time getting to work right when water levels are always changing in the chamber); chamber 3 on the 29 has Chemi pure and Purigen bags. And I have just the stock pumps in both. The 14 gallons 50 watt heater is in the main tank. Temps average at around 78-79 degrees in both but can climb to 81 or so during a warm day.
Both have stock lighting but I have added 2 Reef Brite mini Mags for added light and nice shimmer on the 14 gallon and a Stunner 50/50 strip on the 29gallon to help simulate dusk and dawn. Dawn starts at 8am and the stock lights for 14 gallon at 10 am and 29 at 11 am via timers and then they both go out at 7pm and then dusk is off at 9pm.
Both have a Hydor Koralia Nano powerhead, about 1 lb of live rock per gallon arranged for good flow.
I added dry sand not live sand in both. I have many corals but only my softies such as Zoas, star polyps, and clove polyps are doing the worse or even dying off a bit...though I haven't lost anything completely just yet.
My LPS like neon green candy cane, or my Aussie Blastomussa, or my chalices and Duncans are all doing great. I even have a SPS Meteor Shower Cyphastrea doing awesome and growing in my 29. I have 1 fish in the 14 gallon (yellow tailed damsel) and 3 fish in the 29 (2 clowns and a green Chromis). Also, 1 snail and a blue legged hermit in the 14 gallon and 3 snails in the 29. I know my CUC is understocked in both tanks but for some reason I had a die off on half of my snails in both tanks about 1 1/2 months ago and don't know why.
<Lack of food for them is likely, too many for that volume.>
Maybe sick Zoas were leaching toxins in the water?
<Likely some allelopathy going on here and the Zoas are fighting back.
It's really not a good idea to mix Zoas with SPS/LPS corals in small systems for just that reason.
May want to read here as well.
Water changes are weekly, about 10% in the 14 gallon and 5% in the 29. I use Reef Crystals for my salt mix and my own SpectraPure ro/di water made here. I use a turkey baster to blow off the live rock about every other day or so, when I get in there to scrap the algae off the glass.
My parameters
-salinity is just about 37 ppt
-PH stays about 7.7 but I've seen it as low as 7.5
-Ammonia has always been around 0
-Nitrites 0
-Nitrates 0

-KH 196.9
-Calcium (last checked 520+ in my 14 gallon)
-Phosphates 0 to an occasional .12

<Even though your nitrates are non-existent, most corals do appreciate a low level of nitrates in the water. Somewhere around 5ppm would be good.
Low nitrates help control Cyano to an extent, but Cyano is fueled more by dissolved organic carbons and this is where an efficient protein skimmer is beneficial. Purigen and Chemipure won't help too much in removing DOCs.>
Like I said, I have no idea what the cause of either could be and am getting very frustrated and even a little disappointed. I love this hobby but only understand the basics of it. Your website helps me greatly to understand things much more and I'm very grateful for it. I'm now a bit afraid to go on the forums and ask about my problems here because I know I'll get a thousand different answers. So I'm coming to you and asking you.
Please, please help! Thank you, WWM!!
<You're welcome. James (Salty Dog)>

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