Zoanthid Mortality, A discussion

[MUCHO REEF]

We've all experienced this at one time or another. A frag or colony that has prospered for weeks, months and yes even years, yet suddenly it rapidly declines. Often it begins with a single polyp, a small cluster of polyps, or the entire colony that won't expand. Zoos that are of mat form ( very short polyps extending roughly less than 1/4" ) begin to cup and slowly dissolve. Zooanthids and Palythoas with longer tentacle will also retract, followed by stems ( stolons ), which appear pinched and collapsed. Often zoos will retract for short periods of time as a means of cleaning themselves externally, this is very normal. I have experienced this many times, but the colony always springs back to life in less than a week. As long as the polyp retains its natural appearance, its texture, with no odor, no visible signs of decline ( flaking off of tissue/rapid degradation, predation, bacterial infection or fungus, it will be fine. The key however is recognizing the difference between the two. Just because a colony is retracted, it doesn't necessarily warrant a dip. Close visual inspection in the tank as well as outside of the tank is the best action to take.

Lets say you have a 4" x 4" colony of pink zoos, in the center of the colony you have 6 polyps that are retracted. Should you dip? NO. That is a sure sign of an irritant, a snail, a crab, etc, but not necessarily a predator. I would be dipping constantly if that were the case in my tank. Inverts will crawl over a zoo and the retraction will appear the same as it would a nudi or a Sundial snail. If it were a nudi, several polyps if not the entire colony will retract. If I'm not sure, I slowly remove the colony to inspect it and dip just for piece of mind. However, it you have 6 polyps that are retracting and there's something on your polyps that is so small that you can't determine what it is, Yes, dip that puppy ASAP. Knowing which zoos that are prone BI is equally important. I found a stunning pink colony two weeks ago at a LFS. The colony/rock was the size of a football and loaded. The price was $ 115 and loaded with hot pink zoos with yellow eyes. I'm sure many of you are aware of this morph. Well, it's prone to BI and fungus. Knowing this, I told the store that I wanted to buy it but I would come back next week since it had just arrived a few days earlier. I knew from experience an awful lot about this morph. I expressed to the person helping me exactly what I've just stated about this morph. Well, I went back last weekend, yep you guessed it, there were 3 patches of BI a full 1 inch in diameter each on the colony. On the left, the far right and the very bottom of the face of the colony. The only hope to save it is to frag it, surgically remove all of the BI plus 3 surrounding rows of zoos, followed by a dip. I could have blown a $ 115 on a colony that I would have had to fight to save. Mind you, it was perfectly healthy just days before.

Getting back to the topic, so what causes this rapid onset of failure. Is it a deficiency, a parameter that's too high or too low, is it salinity, is it a lack of current. Could it be P.A.R values ? Or...................could it be stress related. Is there a common thread that all of use share who have lost a colony that was otherwise perfectly healthy. Ruling out those colonies which are placed next to more aggressive sting corals. We're talking about a single healthy colony sitting dead center of other healthy zoos. I would like to hear what my fellow reefers think about this. Does anyone have any supporting documentation or success with reversing this process? What are your speculations? How did it progress in your tank? Is it something we did?

I have a question, does anyone use a power head to blow off your zoos once a week? Sounds crazy ? Grab a Maxi jet 900 or 1200 and blow off your colonies and see what happens.

Lets discuss this and see what we all have/had in common when a zoo colony suddenly died for no apparent reason. Could the answer be right here?

Mucho

[MarvinsReef]

I'm a fairly new zoa collector (inspired by Mucho's TOTM winning zoa/ric tank).. I'm very excited to learn more about zoas so this is a great topic for us novices...

Sorry, no input as of yet.

[Nuhtty]

Mucho

I would like to thank you for starting this thread...very important topic IMO.

I take a turkey baster and "Wash" my zoo colonies at least twice a week.

I dont blast them because I dont want them to close up right away.

I give them a few gentle currents then I will be more forceful to get any other stuff that may be between polyps.

Thus far (knock on wood) I have never lost a single zoo. Some of the colonies I have double and spread rapidly and there are others which have literally only gained a few polyps in 8-10 months.

I have also had good luck in my tank with polyps that other people said were dead...a few days, sometimes weeks, in my tank and wouldnt ya know it...polyps start opening up.

I do FW dips on all new arrivals, whether from a friends tank or not and meticulously inspect each individual polyp (MUCH easier with small frags!!) for anything I dont like.

I pluck any questionably polyps...sometimes I get more carried away if I have a large frag to play with.

Anyway, thats my habit...not sure if there is any reason to my madness, but thus far it has worked well for me.

In about 2 months I will be moving from 4x39w T5s to 2x250w MHs with Actinic VHOs.

I dont expect any issues...in fact I expect even more growth.

[tekknoschtev]

On colonies that I can pick up and visually inspect (the ones that havent spread to another rock and would require tearing them off to do so) I pick them up and take a powerhead and wash them. Its amazing the crap that comes flying out the holes in the rock some times. The powerhead I use is a JBJ 1800, so its about 300gph. I do first fan the colony to get the polyps to close up. On colonies that are too large or cant be disturbed I bring the powerhead to them.

::knock on wood:: I havent had any of my large colonies start doing what you have described, however, I did have a colony I purchased go south pretty quick. Even fragging and dipping didnt save them. I did save three frags though, that hopefully will grow out. I did have a frag of about 20 polyps of Ked's Reds develope a white fungus like growth on them and they for whatever reason started to fall apart. I ended up fragging them onto three rocks. One rock contained the zoanthids with the white splotches on them, and the other two were the clean zoanthids. All of them made it. So who knows.

Correction - I did have that happen on my first colony of zoanthids. 4 months into it, they just started dissapearing. Everything else was fine. I wasnt home to do a proper analysis of the problem, so my mom placed them in a 20gal tank with no lighting for 3 days. Put them back in the display and now the colony is back to full size again. Odd.

[MinibowMatt]

Great thread...
I have not exprienced a total colony loss yet either, except for a new arrival from the west coast. they were blues, came in with infection, i fragged them off about where mucho stated-- 3 rows away from the infection. The colony was still a loss. I was new to reefing then, so maybe i could have done more. I do blow my zoos off every two weeks or so with a turkey baster. My tank is small, and if i used a PH i would have sand all over.. I have had some major crud come out from tight zoo colonies, and loose ones alike. I think their has to be some correallation between crud between polyps and colony loss.

[Mantis737]

I lost a colony of reds this way. Very crappy indeed. I dipped after about 1/4 of the colony started to stem-up. It was odd, one closed in the middle, then the rest followed and got hard stems rather than a poylp. Don't know what caused it, and it's the only ones that I have ever had do it. Another guy that had the same zoos told me the same thing happened to him when the colony got to be the same size as mine. Very interesting, and I would love ot get some more info on it.

[MUCHO REEF]

I think it's important that as many reefers as possible respond and share your experience with this. We would all greatly appreciate it.

Thanks

[spidey07]

Well as a newb I can only offer my experience. I lost an entire colony. Yet 4 others are as happy as can be.

Things I've noticed.

How closed are they? If fully, meaning it looks like a little nub then it is cause for concern. If partially, meaning you can see a very small opening of the polyp that is much better.

And the biggest thing I've noticed in healthy vs unhealthy colonies is the "recoup" time. My very healthy zoos can have a crab on them or being handled or any physical irritant and they retract rapidly and consequently open up rapidly - meaning fully opening up within 60 seconds. Those that are not so healthy take much longer.

[Nuhtty]

Originally posted by spidey07


And the biggest thing I've noticed in healthy vs unhealthy colonies is the "recoup" time. My very healthy zoos can have a crab on them or being handled or any physical irritant and they retract rapidly and consequently open up rapidly - meaning fully opening up within 60 seconds. Those that are not so healthy take much longer.

This is a really good point.

I have noticed that a few of my colonies "frag" better than others as well...meaning when I put them back in the main tank after being on the chopping block, they open within an hour or two.

Some (albeit not many) colonies take almost the whole day.

I try to frag in the am so that the frag has the rest of the day with lights...not sure if thats a good strategy or not.

[tekknoschtev]

I guess that I've noticed mixed results in respect to that. My latest colony came in, and smelled like death. Upon inspection it had sediment packed tightly between each polyp and there was a great deal of flaking 'skin' and decaying polyps on it that I didnt previously notice in the store. The odd thing is that the zoanthids were opened in their tank, in the bag of water on the ride home, and the ones that closed when I picked the colony up for the FW dip opened up in the freshwater... I've never had that happen before. Its not that they didnt close - they actually opened up when in the freshwater. Within a week, all that remained were three frags (I fragged the entire colony in hopes of saving it).

I have noticed that as a generality, the healthy zoos opening faster though.

[spidey07]

heh, tell me about it.

I can took one of the rocks out with hundreds of zoos on it. ran it under tap water, popped off some bubble algae and what not. let it sit on the counter for a while and plopped it back into the tank.

they were fully opened within 5 minutes. And this is the one I've yanked many nudis off of.

[metalManiac]

well, been looking at my zoos, and for the past few days one colony was just getting really thin (the stalks) but the top was kinda trying to open, i didnt know why, but thought it must be one of those spontaneous deaths that you never really know how it happened.
So today im looking at them again and a see a friggn nudi head sticking out of the base of the zoo! little *****, no wonder i couldnt see anything wrong with the colony. the bastard was going at it from the inside out!

Well, i decided to throw away the whole colony of those zoos (they all loked skinny), better be safe then sorry!

Oh and btw, i took a scalpel to that little bastard of a nudi and turned him into mincemeat!





just a warning, sometimes theres more to it than spontaneous death!

[Nuhtty]

Yeah...nudis can be tough to spot

[Kirklan]

I've had 2 different colonies melt away on me. 1 I had a flat worm problem in my nano and they got completley covered by them in a couple of days. Even after eradicating the flat worms, I could never get the colony to fully open up and they slowly wasted away.

Another colony I had for quite a few months up towards the top of my tank right under a 250w halide. The bulbs were needing replaced and I purchased XM 10k's. None of my SPS coral burned, but my zoos melted away soon after.

[BrokkenTWolf]

I've had one colony slowly die on me. Sometimes polyps would be extended and the next day for no apparent reason, they'd be completely closed off while the rest of my zoas appeared unaffected. Eventually, I had less than 10 polyps and they started looking white and slimy. For the sake and health of the others, I ended up throwing the frag away. Dips did nothing for this colony. It was intent on decline no matter what.

As for 'housecleaning' my zoas. I take a pipette and "blow off" residue and other nastiness that accumulates in the zoa colonies. Amazing the amount of stuff that collects in there! Any idea what that residue is? Is it a byproduct of the zoanthids?

[Nuhtty]

Originally posted by BrokkenTWolf


As for 'housecleaning' my zoas. I take a pipette and "blow off" residue and other nastiness that accumulates in the zoa colonies. Amazing the amount of stuff that collects in there! Any idea what that residue is? Is it a byproduct of the zoanthids?

I just think its particle matter from the tank that lands on the zoos and gets mixed with the corals natural "gooey" cleaning slime...or whatever its called!

[lvreefer]

I have something going on right now on one of my colonies. I plan on pulling it out to get a better look at it. By the way I use a baster on all of my corals and rock once a week. Its unbelievable how much settles on the rock in one week. I'll take a pic and keep you updated.

[lvreefer]

So here's a pic...

They have been closed now for two days.

[MUCHO REEF]

Wow, I thought a lot of reefers would want to play a part in sharing their experiences with their zoos dying. Hey maybe I'm talking too much !!!

Mucho

[MinibowMatt]

LVreefer.. have you checked for nudis?

[GovtCheese]

Originally posted by MUCHO REEF
Wow, I thought a lot of reefers would want to play a part in sharing their experiences with their zoos dying. Hey maybe I'm talking too much !!!

Mucho

I just get totally bummed out when I think of the countless number of zoo colonies of various colors, melt away or get munched on by my hippo tang, which I have affectionately named "the eating machine"

[BrianPlankis]

Mucho,

I'm very interested in this thread, I hope more people continue to respond to it. I'm curious because I can't seem to keep pink zoas of any morph alive in my tank and I'm starting to think I shouldn't try any more.

The process was very similiar in both color morphs I tried:

1. Both came as frags with 10-20 polyps on the frag. Both appeared healthy and had been living months in the frag supplier's tank. Different suppliers. One colony was over 2 years old and fragged multiple times.

2. Both appeared healthy in my tank initially for about a week with all polyps opening. Both were treated to your RC zoa dip before being placed in the tank.

3. About 1-2 weeks after placement in the tank one or more polyps start to close. Within a couple of days very small white dots appear on the closed polyps. The white dots never get bigger, just more numerous. They are not nudibranchs or their eggs. The skin on the closed polyps appears to start shedding and then the polyps begin to shrink until only a mat is left.

4. The mat slowly disappears or parts will flake off in the water column until nothing is left.

5. RC zoa dips were done again on both frags. The first time it was just one dip, the second frag it was one dip per week. No known described predators fell off in any dips. All other zoas were fine during this time, no losses and I have 20+ types of zoas in my tank. In fact most zoas were showing very good growth.

6. Water parameters were in the following ranges during the losses. Average reading in ()

pH: 8.0-8.3 (8.0)
Salinity: 1.024-1.027 (1.026)
Ca: 350-450 (400)
Alk: 6.0-11.5 (I've been slowly raising this to 11. It was mostly in the 8.0-9.5 range)
Mg: 1200-1400 (1350)

All other readings were zero (Ammonia, Nitrite, Nitrate, phosphate are what I test).

Brian

EDIT: Oh yeah, I keep them under 2 - 175W MH 10K and 2 - 110W super actinic VHO. The first frag came from midway up a tank with 400W MH, so I'm curious if the reduction in lighting ended up killing them.

[MarvinsReef]

I'm also curious about the white spots on zoas.. I'm starting to experience this on our green (yellow skirt) colony... I did a FW dip on them last week and no sign of nudi's or eggs.. just small white dots... the polyps still are not doing well.. I will post some pictures of them when I get back this weekend..

Any insight about this will be appreciated...

[Grimstalk]

after reading this thread I decided to dip one of my small colonies which hasn't seem right for the last few months. I decided to do the FW dip.

Anyways, first thing I noticed, underneath the zoo was a black snail. Black shells, new to me?? Also attached were a few other snails which came off. Also found a small bristle worm.

I think bugs/snails etc were lodging themselves inbetween the rock and the zoo colony which is encrusting the rock.

[MarvinsReef]

does it look like one of these.. if it is, good thing you caught it.. they make zoas their snack

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