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Mandarin Disease FAQs: Social 

FAQs on Mandarin Disease by Category: Diagnosis, Environmental, NutritionalInfectious, Parasitic (see also: Mandarins/Blennies/Gobies & Crypt,), Trauma, Treatment

Related FAQs: Mandarin Disease/Health 1, Mandarin Disease 2, Mandarin Disease 3, Mandarin Disease 4,
Mandarins/Blennies/Gobies & Crypt, Psychedelic "Gobies"/Dragonets/Mandarins & their Relatives 1, Mandarins , Mandarins 3, Mandarin Identification, Mandarin Behavior, Mandarin Systems, Mandarin Compatibility, Mandarin Selection, Mandarin Feeding, Mandarin Reproduction,

Related Articles: Psychedelic "Gobies"/Dragonets/Mandarins, real Gobies & their Relatives,

Mean tankmates, ones that outcompete your mandarin/s for food...

Much stinging-celled life... can/will sting, consume these fishes.

Mandarinfish Bleaching? Untenable mix of Cnid.s in a small volume      1/21/15
I love your site and have read the threads on Mandarinfish but not sure it applies to my Mandarinfish. We have a 29 Biocube that has been reef established with live rock and sand for 5 years. We added just a few fish in the last couple of months. Yellow tail damsel, 2 ocellaris, 1 Mandarinfish. We bought the Mandarinfish 5-6 weeks ago and we have bought 3 additional bottles of copepods in that time to make sure he has plenty. He is fading and the lateral lines are showing on his back but he doesn't look like he is starving to me, however, I obviously am no expert.
<Doesn't appear overly thin; but I do see the whiting out in the anterior
His color is dramatically fading in the last week. He did have a stressor  about 1 week ago. We found him in the sump and had to net him out. He did take a few days to recover from that but after 36 hours, he was swimming around picking pods as usual. He pecks about every 4-8 seconds so I assumed there were/are enough pods for him. Does he look like he is starving?

I am getting another bottle of pods tomorrow and have picked up some Chaeto to seed again too. Please help me figure out what is causing this and what I can do to help/save him. We just love our little guy.
We are dealing with a little bit of Cyano,
<This is another stressor>

with the addition of the fish, I overfed :( We are currently correcting that.
Candy Cane Coral
Frogspawn Coral
Leather toadstool
Trach brain
LTA anemone
<Yikes... and the anemone mixed with these stony and the Sarco in such a small volume... You'll need to do more to counter the allelopathy going on here. Do read: http://wetwebmedia.com/CorlCompArt.htm

and the linked files above>
All coral are frags and small except the Acan
PH 8
Salinity 1.025
Phosphates 0
<Your photosynthetic life requires some>

Ammonia 0
Nitrates 5-10 (a little high right now)
<The reading for now; and patience. Bob Fenner>

Re: Mandarinfish Bleaching?      1/21/15
I love you; thank you!
I'm so glad he isn't starving. I will read and
correct whatever I need. We have ordered your book and are trying very hard to be conscientious aquarists. We are setting up a 90 gallon and will transfer anything that is not compatible.
Thanks, again.
<Ah, welcome. BobF>

Re: Mandarinfish Bleaching?      1/22/15
Hi Bob,
I'm April's husband Chris (love your site too!) and we're working together
tonight to separate out some of our corals/anemone in a refugium to create a frag only tank to counter the allelopathy issue.
<Ah, good>
We've been reading the
resources you've provided and the concept is well spelled out in that we do appear to have created a "chemical soup" from the corals and anemone in a small tank.
<Yes; quite common w/ such "coral garden" approaches>
April was giving you a list from memory and I was hoping to
get you help in how to divide up the corals between the two
locations...basically split the list in two (or does it not matter which in
particular go where, just reduce the number in the tank).
<Does matter... Not knowing your background, but if you have had much chemistry: Like a RedOx listing of elements more/less likely to "steal"/"get robbed" of electrons, there are very aggressive species (e.g. the Halogens, Fluorine...) in the way of allelopathogenic species (e.g. Galaxy Corals, Oculinids) and on the other end of the scale "losers" like the Alkaline Earths (Ca, Mg...) in the way of Stony Corals things like Pocilloporids, ... with a range/scale all in-between. Of what you have the Euphylliid and polyps are top dogs, along w/ the anemone...>
Here is the full
Candy Cane Coral
Frogspawn Coral
Leather toadstool
Trach brain
LTA anemone
Majestic Anemone
Daisy Polyp
Short stem Goniopora

Again, most of these are fairly small frags with the Acan being the biggest
at 7"x4" and the Trach is about 4 inches long.
We want to deal with the allelopathy quickly for the mandarin and then
decide what to do with the corals (new tank or sell) as we continue to read and research more.
Thanks so much.
<I'd trade out the Anemones immediately; as they are the very most incompatible organisms with all else here.
Bob Fenner>

Clavularia strangling Zoa? 1/15/11
Hello WWM crew. My first email after many, many hours searching and soaking up the knowledge from your site. Thanks much for your team's dedication to the betterment of this hobby and its hobbyists.
<Welcome Tommy>
I'll forego the tank description this time as this is more of a general behavioral question - I have what I believe are Clavularia (daisy/star polyps), and as advertized, they are quickly multiplying and extending their dominion (so far not a nuisance, but I'm wary). They've latched onto a small Zoa colony that was in their vicinity (see attached picture), and I'm wondering if I should take action to separate them.
<Mmm, is this possible, practical?>
Neither has shown any signs of illness from the connection thus far, but will the Clavularia eventually strangle or otherwise envelop the Zoa?
<Mmm, seem to have come to some sort of agreement from your pic>
Also, if I were to separate them, what is the best way to go about doing that without injuring either creature?
<I would leave them as is... if one is going to overgrow the other...>
Actually, I'd mainly be concerned about injuring the Zoa, as it only has about 7 polyps, whereas the Clav probably wouldn't suffer from losing a few of its 40+ stalks.
Thanks again for all the valuable information. It is much appreciated.
San Francisco, CA, USA
<Bob Fenner, San Diego, Cozumel/QRoo>

Mandarin... hlth., poss. chewing by Isopods 2/20/2010
Hello all you fine folks at WWM.
<Salud Frank>
I have an issue with my green mandarin that I'd like to get your thoughts on. The mandarin has been my favorite fish for about 10 months now. I originally had him in my 75 but my girlfriend is moving in so in order to save a little space I downsized to a RedSea max 130d (34 gallon total volume I believe) all in one setup. I kept a few pieces of my live rock and about 2 cups of the live sand for this setup to which I added some new live rock (smaller pieces for smaller tank) and a new bag of CaribSea live sand (the black variety). All my water parameters check in at desirable levels.
PH = 8.3
Amm = 0
Nit = 0
Nitrate = 5-10
salinity = 1.025
cal = 420
Anyhow my problem is that since adding the new live rock I have noticed some little critters that resemble rolypolys only smaller.
<Mmm, could be real trouble... most (if this is what they are) Isopods are predaceous... Read here: http://wetwebmedia.com/isopodid.htm>
I dropped in a few shrimp pellets for the mystery wrasse and scarlet cleaner shrimp who made the move to the smaller tank along with the mandarin and as the pellets disintegrated on the bottom these little bugs were foraging thru it and presumably having a meal. I have read about the dreaded isopods on your site and made the assumption that I must have the scavenging type since I have never seen them on any of the livestock.
<Oh! Thus far...>
Well a couple of days ago I noticed my mandarin's lip looked odd and tried to get a better look at it and in doing so noticed that his tale had apparently been nibbled on as well as having a smooth looking tear in it as well as a tear in his dorsal fin. I am wondering if this is due to a parasitic isopod and curious if one has latched on inside his lower jaw causing him to look like he has a fat lower lip.
<Mmm, maybe. This or something else>
I cant get a good look and he is very shy so I couldn't get a picture for reference but he is still swimming around and hunting for food on the live rock as well as chowing down on frozen Mysis and brine shrimp as well as blood worms all soaked in Selcon. He has always been a good eater but almost seems to be eating more. The thought also crossed my mind that he could have been stung by one of my coral frags (sun coral frag, green button polyp frag, and Sarcophyton?)
or a small Aiptasia or some sort of anemone that came in on the new live rock that is clear but don't look like Aiptasia. Anyhow sorry for the long read but I was wondering if you might be able to offer some advice. Any
would be greatly appreciated.
Thanks a lot, Frank
<You've about covered the most promising possibilities. Keep your eyes open here. Bob Fenner>

Mandarin acting oddly 5/13/07 Hi there, <Carrie> After waiting about 1 1/2 years, I purchased a large mandarin male about 3 months ago for my 150 gallon reef/fish aquarium. I had tons of copepods (big fat ones) and a fishless refugium going, so food is not really an issue! I noticed sometime last week, he was not "hunting", but still. I foolishly thought, wow, he must be full, besides he is not thin and was fatter than when I got him! So after another day went by, I was a little concerned as it was just after lights out (timer on tank) he was in his "lightened" phase of sleep colors, but would go up and backwards (kind of like he thought someone was following him if that makes sense) and acting odd. Today, I looked over at my tank and noticed he was at the top of the tank spitting water. I took some pictures to help you out. Behind his eyes are swollen. Do you have ANY clue what this could be? <This fish appears to be "burned", stung by something... likely biological... could be from a bunch of possibilities... Fireworms (come in all sizes), jellies of various sorts... a blundering into a stinging-celled animal...> I put him into the refugium, even though no one was bothering him, just so he could "chill." <Good move> Thanks!
Carrie :)
<I do hope he recovers. Bob Fenner>

Attn: Bob - Mandarin QT... Hey, I'm not going in with that Callionymid! 7/18/06 Hi, We have received great advice from you in the past! You helped us through trying to save our female mandarin (but she was apparently too far gone to start with). Our male Green Mandarin is now very, very fat and healthy in his 230 gallon kingdom. <Ah, good> We were given 2 females after a tank tear down that have now been in QT 10 days. The QT has about 30 lbs of live rock seeded with copepods (a few months ago). The little Green female seems well rounded. The other female is a 3" spotted that they had not had very long. Her belly is slightly convex - but seems to be getting flatter. She is eating great (seems to nab a pod about every 5 seconds - although they are too small for me to see). They get along great - not even a hint of a squabble! <Good> Our plan is to switch out the male for a short period to get the females used to the big tank and to hopefully prevent the male from being completely territorial. That is, if we can catch him while he is asleep - otherwise we'll never get him out. A couple of questions: 1) Does switching them out temporarily seem like a good plan (I really hate to disturb the male, as he is so healthy and outgoing - but I fear he will not accept strangers in his territory otherwise)? <I would try just introducing both the females simultaneously "by cover of night"> 2) How long would we need to keep him in "exile?" <A week or so if you were to try this> 3) Is it okay to shorten the females' QT period? No signs at all of ich or disease so far (just the slightly sunken belly of the spotted). If so, I'd love to go ahead and do this so that everyone will be in the big tank before our vacation, which is in a week. However, we can leave them in QT if necessary. We've been monitoring to ensure they are eating consistently and have 2 copepod cultures to supplement the rock if necessary while we are home, but that close monitoring would be impossible while we are gone. <I am a believer in not long-quarantining certain groups of animals... Including dragonets. I would foreshorten QT here if all appears as you state.> Thanks as usual for your advice and time!!! - Doug <Welcome. Bob Fenner>

Wherefore art thou Geisha/Mandarin? 8/27/05 Thank God for WWM! You guys are great...however I was hoping I'd never have to e-mail you again.... After searching around your site, I am still unsure of how to handle this. I have a 100 gallon bow front with 110 lbs of live rock, all of the levels have checked out... perfect. <?> Occupants include a Chocolate Chip Starfish, 1 Coral Banded Shrimp, 2 Blue-Green Chromis (used while cycling still around), a True Percula, 1 Saddleback Anemonefish, a "red bulb" Anemone (that's what the LFS said), a Yellow Tang and 2 Mandarinfish (a male, Sumo and a female, Geisha) Everything has been going great since the tank has been set up, except a brief issue with the Tang over a month ago, in which you all helped me eradicate (a freshwater dip). All was well in my "Peaceable Kingdom" UNTIL....(I guess you knew that word was going to pop up sooner or later) My female Mandarinfish disappeared. Actually I didn't realize she disappeared until this morning, however once I began putting 2 and 2 together she has probably been "out of sight" for at least 2 days now. Yesterday I noticed my male mandarin swimming up and down the side tank wall, not munching on food there, just sort of solemnly going up and down...later on , he continued his normal activities...in retrospect, Geisha, the female wasn't with him... which at the time didn't register, I was more concerned with his odd behavior, but once he settled back to grazing and what not, I didn't think any more about it. This morning I came down and turned on the "daytime" lights in the tank and he did the same thing for a couple of minutes then went on with "normal" activities. Still, I didn't think anything of Geisha. These two have been so hardy for us, even though everyone warned us, it just never dawned on me that there was an issue. After cruising around on your website, as I normally do in the morning, I was reading an FAQ about a Percula that just stayed in the top corner of the tank, only venturing out to eat...I thought, oh, my Percula does that all the time, I should read on...the answer stated that the Percula was just lonely and checking out his reflection. Bingo, suddenly it all came together....could that be the cause of Sumo's strange behavior? <Mmm, unlikely> I immediately went to the tank to look for Geisha, I didn't see her and started thinking about when I saw her last, approximately 3 days ago when I was adding a new live rock, a Squareblock Anthias, and a small Brittlestar (rust & black in color with a black disk) The search for Geisha started around 10am today and still no sign of her, totally abnormal when coupled with the fact I don't recall seeing her at all for the past couple of days. My question to you, should I do a "full fledged archaeological dig" moving rocks and stuff? <I wouldn't> I hate to upset everyone and get them all stressed out, however if she has fallen ill and hiding I want to try and help her (however that would be strange for her to just get sick out of the clear blue when she has always eaten well and been very active). Also, I truly believe the anemone is innocent, <... innocent? Of consuming this fish? Is most likely it did> even though she is large she eats well 3 times a week and is closely "guarded " by the saddleback. I don't recall ever seeing the Mandarinfish in that area of the tank. Also, in defense of Emily the Anemone, she has been wide open during the day, and hasn't emitted any indigestible "goo" plus her stem is almost translucent and when she eats "spaghetti" once a week (a driftworm) I can see it in her. Surely the voluptuous Geisha would show right through. If Geisha has indeed passed on, will her rotting corpse totally screw up my levels, if I don't locate it? <Doubtful> I have about a dozen blue legged crabs and the same amount of turbo snails that are complete scavengers. Any ideas would be highly appreciated. Thanks in Advance, Amy <This fish is likely gone... died, dissolved, consumed... by what? Bob Fenner>
Geisha the mandarin, discovered gone 8/28/05
Bob, Unfortunately I was correct, Geisha was found dead behind a large rock shortly after I sent you the e-mail, it was rather strange, her coloring was still amazingly bright but it looked as though she had been "filleted" do you think it's possible that my overly aggressive and large (9"from tip of antennae to tail) coral banded shrimp may be at fault? <Yes, possible> He is always waving his claws around and taking a nip at all who pass him. I think the behaviour that her mate showed after her demise is rather interesting from a fish socialization standpoint. Fortunately she was close enough to the heater that when I gave it a gentle pull it washed her body up so that I could net her without disrupting everyone. I appreciate your knowledge. Thanks, Amy <Thank you for this follow-up. If you'd like, you can read re other folks mis-adventures with at-times aggressive CBS, on WWM. Bob Fenner>

Mandarin health Dear Crew, <Hello, how are you??> I have had mandarin fish (Synchiropus splendidus) for 6 months and he has been fine feeding on frozen foods until yesterday morning when he just sits motionless in the tank with fins erect with laboured gill movements but no other sign of infection. Ammonia, nitrite are 0 and other parameters are stable. Other occupants of the 125 litre tank with live rock are 2 cleaner shrimps, 2 black footed clownfish and various soft corals. All other occupants are fine. I have never known a fish to change so quickly with no apparent reason and to have erect fins as a symptom. Any ideas? Gordon <Hello, Gordon. I do have an idea. I think that the mandarin might be getting picked on by something in the tank. It doesn't have to be fish related to be picking on the mandarin. It could be that there is a crab or shrimp that are bothering the fish. The dorsal fin being erect is usually a defensive posture in most fishes. You mention that the other parameters are stable, does that include the PH? One other possibility could be that the fish could be coming down with something called marine velvet. Check for tiny "sugar like" spots covering the fish. Good Luck. MikeB.>
Re: mandarin fish
Hi Mike Thanks for that. In the end he actually seemed to get better himself and now seems to be doing what he was doing previously. As for something chasing him it could have been a mantis shrimp that I discovered in the tank a few weeks ago that could have had a go at him. I subsequently caught the shrimp yesterday (about 2 inches long and brown) and so hopefully he won't get hassled from him. Shall keep an eye on things and let you know. Cheers. Gordon <Gordon, thank you for the kind words. They bring a smile to my face and brighten my day!!! Keep me posted. MikeB>

Mandarin Dragonette and color loss Bob and Crew, <Hello Deborah> Regarding this phenomenon: "Ok, so the problem...Yesterday after changing the usual 10 gallons of water and cleaning the algae off the sides of the tank that I do every week for the last year, using Instant Ocean synthetic sea salt, I looked at my tank after about an hour. The other tank inhabitants seemed fine. The Mandarin was losing color and lying at the bottom of the tank. Its beautiful colors were changing to kind of bleached light peachy splotches with some areas of regular color. It also did not move. It seemed to deteriorate for a couple hours, continuing to lose color, breathing looked different, and didn't move much. Then after a while it was hunting, and eating, all color back and now looks fine. I do not want to go through that again. What on earth happened? Is that common? <My guess/bet is on a chemical and/or physical challenge that arose from your polyps (or mushrooms) consequent to the water change... Do you pre-mix, store your new water ahead of use? Please see here re: http://www.wetwebmedia.com/water4maruse.htm < http://www.wetwebmedia.com/water4maruse.htm> and have you read over the Mandarin FAQs materials archived on WWM? I would: http://www.wetwebmedia.com/mandarins.htm < http://www.wetwebmedia.com/mandarins.htm> Find them linked, at top, in blue> Thanks, Flo <Bob Fenner>" as published at http://www.wetwebmedia.com/manddisfaqs.htm < http://www.wetwebmedia.com/manddisfaqs.htm> . I am writing to tell you that we experienced exactly the same thing this morning. We have had an ill seahorse who was treated and then returned to the tank yesterday. Sometime during the night she died. This morning we woke up to this bleached-out mandarin. An hour later, he was his normal self, swimming around just fine and quite colorful. We have had this mandarin for 2 months and he has always seemed healthy and fat. Our tank usually has plenty of 'pods, although I've noticed their numbers down over the past few days. Our parameters were all perfect when we measured them and no new fish have been added to the tank. We age our water before changes. There are only 2 corals in the tank (1 leather and 1 clove polyp) both doing well. I'd be interested to find out if other people have experienced similar incidents with mandarins to try to learn if any commonalities might emerge. <Me too. Will post your data, comments in hopes others will come forward. You might also send this note to reefs.org, reefcentral.com for a broader input> regards and thanks for providing an excellent web site and information repository! <Thank you. Bob Fenner> Deborah Lafky
Follow-up on Mandarin Dragonette color loss
A while back I wrote you about our experience with color loss in a mandarin dragonette http://www.wetwebmedia.com/manddisfaqs.htm < http://www.wetwebmedia.com/manddisfaqs.htm> . Since then, we had not observed another similar episode despite having moved him from one tank to another and then back again. <When you have a healthy/well fed dragonette, the fish are very "sturdy" meaning they can take being moved to new tanks without fear. I know a couple people that has a mandarin that moves back and forth between tanks every so many months so to allow the copepods a chance to repopulate. Now that isn't suggested, but it shows that the fish is rater hardy.> He is presently back in the seahorse tank where he loves to snap up copepods. Anyway, this morning he had another early-morning color loss episode and again, it was at the same time as a seahorse fell sick (Vibrio). Is it possible that the mandarin is sensitive to biochemicals emitted from the sick seahorse? <Not likely, I've never heard of fish becoming sick from emissions from seahorses. My guess is that there is some aspect of the tank that is not right which is effecting the seahorse and the dragonette. I would check your water parameters ASAP! Ammonia/nitrite need to be at zero, your nitrate as close to zero as possible. Also, check you Alkalinity of your tank, if it's to high it can really effect fish, especially a sensitive seahorse which would show sickness long before a Mandarin.> The mandarin colored up again and went about his business shortly after we found him still and pale. <Many fish have a "Resting Color", when they are sleeping/resting at the bottom. Some puffers will darken/lighten their colors when the rest so they aren't as easily spotted in a weakened state. Some fish will have a color fade after lights are out, you can see this if you check you tank out late at night with flashlight. So, the loss of color might simply have been your dragonette in it's resting coloration. I still would check your parameters and make sure that there isn't something that is the culprit.> Strange!! Deborah Lafky <Good luck with the fish, and hope everything turns out well. -Magnus>
Follow-up on Mandarin Dragonette color loss
Thanks very much Magnus. We check the parameters on the seahorse tank frequently. It is extremely stable due to its deep sand bed and that we allow plenty of plant growth to encourage 'pods. I think it must be a resting phase coloration as you suggest. One of these nights I'll sneak upon him with the flashlight and see! Deborah <Keep an eye on the fish, he might be sick, but as always it's hard to diagnose via email. Just keep an eye on the little fella just to make sure. You might want to set up a Quarantine tank, so you have one ready and cycled just in case you need one. You will be totally surprised what you were missing when you take a flashlight to the tank. It was suggested to me a few years back, and now I keep a flashlight near my tank at all times. It's amazing to see all the night time crew that you never knew was in your tank!!! good luck.-Magnus.>

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