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FAQs on the Powder Blue Tang Disease Diagnosis

FAQs on Powder Blue Tang Disease: PBT Disease 1, PBT Disease 2,
FAQs on Powder Blue Tang Disease by Category: Environmental, Nutritional, Social, Trauma, Pathogen (plus see Tangs/Rabbitfishes & Crypt), Genetic, Treatments

Related Articles: Powder Blue Tangs, Acanthurus Tangs

Related FAQs: Powder Blue Tangs 1, Powder Blue Tangs 2, Powder Blue Tang Identification, PBT Behavior, PBT Compatibility, PBT Selection, PBT Systems, PBT Feeding, PBT Reproduction, Acanthurus Tangs 1Acanthurus Tangs 2, Acanthurus Tangs 3, Acanthurus ID, Acanthurus Behavior, Acanthurus Compatibility, Acanthurus Selection, Acanthurus Systems, Acanthurus Feeding, Acanthurus Disease, Acanthurus Reproduction,


Surgeonfishes: Tangs for  Marine

Diversity, Selection & Care

New eBook on Amazon: Available here
New Print Book on Create Space: Available here

by Robert (Bob) Fenner

Hairs on PBT    2/13/17
Hi any ideas what these are.. looks like small hairs on my pbt. He has been in tank for about a year. I have been dosing Prazi for the last week. Any help would be great. Thanks
<Would REALLY like to sample and look at these under a microscope... Could be "just" body mucus from... something chem./physically irritating in the water, accumulated gunk in the system attaching... Perhaps some sort of worm/s. Again; I'd sample and look first, check and improve your water quality, add mechanical filtration... and possibly treat with an Anthelminthic... the last via foods. Do please send along further input as this progresses. Bob Fenner>

Re: Hairs on PBT    2/13/17
Thanks bob.. that being said I have a dose of Prazi going now.. I could do a large water change..one other fish may have a couple spots.. not sure.. not sure what to do.. what is your best idea? Environmental or parasite??
<Can't tell w/o data Eric. BobF>
Eric Willoughby
Re: Hairs on PBT    2/13/17

Thanks bob.. another thing he is flashing and rubbing on rocks.. would he do that if it was environmental??
<Oh yes. BobF>
Re: Hairs on PBT    2/13/17

Thanks again.. did a huge wc and loaded a bunch of carbon.. see what happens
<Ah yes. B>

powder blue tang that is bloated     2/27/16
Could you shed some light on the problem I am having with my powder blue tang.
<Will try>
It has looked fine up until this morning where I noticed it was just hovering in one spot, on closer inspection I noticed it was swollen around the abdomen.
<I see this in your excellent pix>
It was a bit sluggish earlier today but this evening it seems to be waddling through the water and the swelling has increased.
<All in one day.... Something ingested... too much, gasifying?>
the pbt has been on a diet of frozen Mysis and brine, Nori, and just recently grazing block.
admittedly the diet has been mostly protein and not a lot of fibre or “green” foods.
<Mmm; should be the other way around>
I have attached a picture to illustrate.
thanks in advance.
<Am hoping "this too shall pass"; however, if it were me, mine, I would go ahead and administer Epsom Salt here; as a laxative... at 1 tsp. per five actual gallons of system water. This is a very safe material; its use gone over and over on WWM if you'd like to search/read. Bob Fenner>

Re: powder blue tang that is bloated    2/28/16
Thanks for the reply.
I have now dosed the tank with Epsom salts and have tried to feed cooked pea’s (skinless) but I have also to hand some “fluke solve” which I am holding off on using until I know whether it will kill of the flatworm infestation I’m having at the moment as well.
<Mmm; are they (the flatworms) "that" bad? I'd leave for now>
I don't suppose you know anything about this?
<A bit; archived on WWM. Do you need help using the search tool, indices?>
adding to this, is it possible to overdose the Epsom salts? what's the effects?
<Not easily done... MgSO4 has a wide margin of safety... again... on WWM. Welcome. BobF>
thanks again

Re: powder blue tang that is bloated    2/28/16
yeah I'm not that concerned about them just now, apart from whether they will die due to the meds. I'm going to siphon a few off tomorrow and do a container test to see their reaction.
these are the flatworms…..I think they are just red Planaria.
<Oh; nice pix. BobF><<Yes, dear browser; this tang may have ingested these. B>>

Disease Identification Hi WWM, <Jen> I need some help identifying some "stringy white tissue" hanging from the fins of a Powder Blue Tang. I have never seen this on a fish before, and have no idea what it is, what caused it, or how to treat it. This fish was quarantined for 3 weeks in hyposalinity and no symptoms of parasite or any other problem was noticed during that time. The specific gravity was then raised over the course of 2-3 days to 1.020, <This species is best always kept in near natural seawater concentration, 1.025> and the fish remained in quarantine for 4 months to help insure he was in excellent condition before being added to the display tank. There were never any indications of parasite or any other problem. He was added to the display tank about 10 days ago. On day 9, we noticed some slight scratching on the rocks and a few of the "stringy white tissue" hanging from the tail fin. On day 10, (picture attached of fish on day 10) he had considerable more of the "tissue" hanging from both pectoral fins, the tail fin and the back part of the dorsal fin. He is still breathing and eating normally. We have noticed that he will occasionally dart, and then resume swimming normally. The other fish in the tank seem unaffected. I am hoping you can help me identify this problem and advise me on the best treatment method. Thank You for your time. Jen Marshall <I am of the opinion that these extensions are part of the fish itself, and will diminish with time, good care. I would not "treat" the water or fish per se. Bob Fenner>

Tang With Ich or Velvet or other? 12/15/05 Hello my wonderful WWM Team, you all are a true blessing! I pour over your information like a wolverine ALL THE TIME to research new tank inhabitants, care, disease, reef care, etc... I true database of information! Here we go. Tank: 29 gallon Bio & Carbon filters, Eclipse hood w/upgraded lighting and add-on circulation unit. About 20 lbs of Live Rock & additional live sand. Tank Inhabitants (currently alive and well): 2 percula clown fish 1 firefish goby 1 clown goby 1 juvenile Powder Blue Tang <... in a too small world... Really needs hundreds of gallons.> 1 Rose BTA <If something goes wrong in such small confines...> 1 SPS Hammer 1 Blood Red Cleaner Shrimp 7 Hermit Crabs 8 Astrea Snails 5 Sand-Sifting Snails (Nass's) I had recently purchased two juvenile clown gobies and a neon goby from my LFS. <Not to go in this same system I hope/trust> This was exactly 18 days ago. Sad to say I have not gathered enough SW care equipment to have a quarantine tank (I know, I know!) - so I acclimated my new tank inhabitants in the only tank I currently own. <You're learning... by fire> The clown gobies fought with each other the first couple days, one becoming very shy and elusive. She used to hide a lot while the other fed (and/or he chased her and they locked jaws a lot, I figured they were sorting things out) but I did in fact observed her eating - have not seen her at all for about 7 days now, was hoping she was still hiding in the LR eating the live food that naturally resided there, but I fear she's gone (crab meal). <Only one should be kept here... remove the other if it's still about.> The neon was very active and aggressively wanted to clean my powder blue tang. (The tang rarely sat still enough for the shrimp to clean him unless he was with it in the rockwork). So he was a great eater, very active, did very "goby things" as I would call it. Then one day (about three days ago) I did not see him during feeding time front and center eating like a maniac. I looked around, he was tucked in the LR and eating here and there, but not like his true self. I did not see him the next day. Today during feeding he must have just died because the crabs were cleaning the fresh carcass (I could see the blue stripes still on him very vividly). I am not sure what he died of at all. He acclimated and got along with everything so very well. Well upon my daughter looking at the remains of the goby. She said, "What's wrong with the tang?" My heart sank - I ran over to the tank. He has what looks like and I can only describe as "chicken pox" - it does not look like ich or marine velvet (to me) but can be either or. How did he get it? <Environmental to a large degree... perhaps a parasite, pathogenic input from the non-acclimated/new livestock...> Could it have come over on the gobies? <Yes> The tang was "flashing" - rubbing up against the rockwork two days ago quite a bit (looking silly I thought - he is quite the character, but I did not notice any spots on him then as I know this can be a sign of a problem). He didn't really have any "white dots" so I looked up black spot - nope not that either. And I am not sure if it is even velvet. They are grayish bumps all over his body. On the dark areas of his face, the spots look like white faded scars, on the light areas they look like a soft gray spot. His white fin on the bottom has what looks like gray spots on it. He is acting very normally, eating, swimming patterns, etc. not getting aggressive towards anyone. I checked my water params and everything seemed normal on my end - but I am taking a sample to the LFS in case I had some sort of error (double checking myself) and salinity is perfect, temp is between 79-81 degrees (usual for my tank). He is not presenting himself that I can see to the blood red shrimp - and did not allow the neon goby to clean more than a few seconds (as he is so active). I heard both of these animals help with ich - is it just my tang is too active to allow for a good cleaning? <Mmm, no> The tang has been in my tank for about 8 months without ever showing signs of sickness except for when I did a large water change once (breathing very quickly - I literally held him in front of the minimal eclipse hood flow I had so he didn't have to work so hard to get flow over his gills. <Good observation> I held him for a few moments in the flow (he actually allowed me to), he was calm and seemed to catch his breath so to speak and I released him from my one-handed cupping and he was fine after that with no draw backs - don't know what that was about but he never exhibited any spotting/discoloration that might have gone along with a disease or infection. Other than that, he has been a happy, healthy and extremely friendly fish to all of his tank mates. <Eight months is a good long time for this species in captivity in general... remarkable in this small setting> He is very bumpy - almost pimply looking. Like I said, appears to be a lot like chicken pox all over his body. They are dull-colored splotches, like I said they discolor whatever color it was on. It made the dark areas appear to be light (like an old scar would be on a person), and light areas have a gray tint. It did not "coat the fish" as the velvet pics show - but had defined spots/bumps. I read and read and read through the tang disease and other diseases and have not found something that fits this description (I did try to do my research!). I thought perhaps with the history of my introduced inhabitants and their behavior/deaths might help you to help me. <... you need a much larger system...> I love my tang (aka: "Fat Head") and would do what's necessary to help him. I have pre-mixed salt at home already with pH buffer missed as well that is about 4 days old. Any suggestions on what I can do now (yes, I am buying a quarantine tank TODAY!) I read you all don't favor copper treatments. Any other suggestions on how to treat the reef tank - and should I remove all the other fish even tho they are showing no signs of the ich/velvet? <Not a treatment per se... but barring moving this fish to a large, stable system with a good deal of cured live rock, possibly "mud filtration", there is not much that can/will "cure" it> I am so afraid I don't know what I am diagnosing and I don't want to treat them, stress them, <You are wise here> then realize I have to treat them all over again for using the wrong medications. HELP! Damage control! (PS: I tried to take some pictures of him, but he is never still and ends up being blurred and you can't see anything. sorry I could not send them along with this request.) Thanks in advance for any help in figuring out what this is and helping me and my fishies - you all are THE BEST and I really appreciate all of the hard work put into having WWM and your selfless contributions to fish-keeping society. Warm Regards and many hugs - Christine <Thank you... am sure you've read my piece on Acanthurus leucosternon posted on WWM, and the accompanying FAQs files... I would review these again. Copper, formalin, other treatment are not efficacious here... this fish needs to be moved to better quarters... soon, to survive. Bob Fenner>

Mystery Malady? Hey Crew! Need your help again! Thanks for your advice! <Glad to be here for you! Scott F. with you today!> I have had this beautiful Powder Blue for 2 weeks now, he has been eating like a monster, and doing well with the other roommates. Parameters: Temp 82 75 gal. w/20 gal. sump/fuge growing Caulerpa; EV-240 skimmer; 140# LR, 4-5" fine substrate pH 8.2 Yellow tang, Picasso Trigger, Volitans Lion, Powder Blue tang NH3 0 NO2 0 NO3 20 <Water conditions sound good...At some point, a larger tank is in order for this crowd!> The last two days the Powder Blue has exhibited the discoloration shown in the photo, he has lost the black to his face. These look like abrasions with some inflammation, but are difficult to visualize due to his speed. <I see...> They are on both sides, and various body parts including his face, which makes me think more along the lines of a fungal infection or such. I'm setting up a Hospital tank now and will QT him until further ID of problem. Thanks again for your help! Ed Carter, RN, BSN, CCRN <Unfortunately, I didn't get the pic, so I'm compelled to take a guess here. Discolorations like you describe could be anything from a non-lethal malady like Head and Lateral Line Erosion (HLLE), which generally is diet or environmentally-induced, to a more serious fungal infection, as you theorize. Usually, HLLE has a gradual onset of symptoms, so you may indeed be looking at some sort of fungal disorder. Are there any other symptoms? Lack of appetite? Heavy breathing? Obvious distress or discomfort shown by the fish? If you could try again with the picture, we might be better able to diagnose this malady. Until then, your quarantine procedure is correct. Keep the water quality high, feed carefully, and take note of further symptoms. I'd avoid any medications until you get a handle on just what this affliction may be. In some cases, these types of non-lethal disorders clear themselves up with the passage of time and a good clean environment. Hang in there! Regards, Scott F.>
This Powder blue I have had for about 4 months. It was at the LFS for about 3 months before I purchased it. It has never had any health problems to my knowledge. Can you determine from these pictures the ailment, if any? <Mmm, nope> I noticed this dark spot on its side 2 days ago. It seems to have occurred overnight. Did it have a run in with some rock? Or the anemone? <Maybe> Or is this some sort of disease? <If so... likely environmental... not nutritional, infectious, parasitic/pathogenic...> The last "change" I made was a 5 gallon water change last week. 90 gal reef tank <Too small> 1.021 <Too low> temp: 80-82 deg Nitrate/phosphate/nitrite/ammonia all equal zero. Lighting: MH and Actinic and moonlights 1 royal Gramma 1 black clown 1 blue damsel 1 sebae anemone (6 inches in diameter when fully expanded) 2 pieces of frogspawn 1 small blue mushroom colony 1 green star polyp 1 leather coral 70-80 lbs live rock Thanks so much for your help, Blake <Could be some sort of allelopathogenic effect... result of negative interaction twixt your H. crispa and the other cnidarians... my best guess... Cures? Improve water quality... use of chemical filtrants, add a refugium... Please read here: http://www.wetwebmedia.com/powdbluetg.htm and the linked files above. Bob Fenner>

Powder Blue Surgeon w/ distended stomach 10/9/04 I've had my powder blue surgeon for a week now and at first he was eating well, but now  he's listless, not breathing well and has a very bloated stomach. I read one of the other FAQs that talked about an intestinal blockage, but I'm not sure if that is what it is. His colour seems normal and there are no outward signs of parasites. Any help with this problem would be great! <if you want to test if its blockage (non-pathogenic), add a heaping tablespoon of Epsom salt (magnesium sulfate from the pharmacy) and repeat at half dose two days later. If you see stabilization or improvement in 3-5 days, carry one with water changes and good feeding. If symptoms degrade, do be prepared to isolate the fish in a proper QT tank for meds. Best regards, Anthony>

Powder Blue Eye Problem Hi, <Hello> I would be grateful for some advice regarding a recently purchased powder blue tang.<Sure, no problem> The tang has been in my reef tank for about a week now. Tank is around 100 gals, been set up about 6 months, occupants are: yellow tang, purple tang, pair of clown fish, blue damsel, mandarin fish.  I purchased the powder blue about 6 weeks ago and asked the LFS to keep it for around 4 weeks so I could ensure it was feeding correctly and disease free.<note, that is not considered a quarantine tank, the fish could be a host to parasites in an uncontrolled environment> I freshwater dipped the fish before introducing it to the tank and have been feeding it on Mysis, "Marine Cuisine" and Nori. Feeding well. <Good plan.>  Today I have noticed a white spot on the centre of its left eye, it has also been offering itself to my cleaner shrimp on a regular basis. Water quality seems fine following my test today. <It could be eye flukes or a fungal infection.  It is hard to tell without a picture.> Would appreciate some advice on next steps please.  <Here is what I would do, take the fish out and put it in a quarantine tank and treat it with the appropriate medication in regards to the sickness.  Good Luck!!! MikeB>

- Singing the Powder Blues? - Hi Crew, I need you opinion regarding whether I should be concerned about my power blue tang.  I just noticed a small grayish patch (appears similar to mildew or a bruise) near its tail (see attached close-up picture).  Typically this would not concern me but I did have a previous powder blue tang that had a similar area that continually expanded until the fish rotted-away.  This previous powder blue tang did have other health issues as its fins were rotting, it had a reduced appetite, a cloudy eye and a near-complete loss of coloration.  This previous Powder Blue tang died in my quarantine tank so the fish in my display tank were never exposed to it. <Understood.> I have had this current powder blue tang for over three months and it has always appeared to be very healthy.  As you can see from the full-fish picture, it appears well (at least to me).  I am just concerned of the possibility that this gray/black patch could be the same problem (just in an early stage) my previous powder blue tang died from.  My water parameters are: Temp: 78 deg F, Salinity: 1.0235, NH3=0, NO3=0, NO4= 5 PPM, Ph=8.1, Ca=380. Does the attached picture provide enough detail to diagnose the problem? <Yes and no.> Should I be doing anything to address this? <Well... I've seen a couple of the lightly colored tangs that are able to turn dark in spots... and it's not always related to their night/fright pattern. I'm thinking of a Unicorn Tang I took in trade that had some spots not unlike the ones you describe and what appear in the photos. The back spots continued long beyond the fright pattern, but did go away on their own in a couple of days. I don't know what those spots were but do think they are related either to color alteration like night/fright or a sign of stress or both. Not certain this is what's going on in this case, but it's worth just keeping an eye on things for now, make sure it is still eating well... get ready to treat just in case... get the quarantine tank fired up.> This fish is in a 180g tank with 200 pounds of rock so catching it is nearly impossible. <Actually not... three 50 gallon Brute trash cans should do the trick. Use a one inch drain hose and siphon the tank into the cans... put some of the live rock in there, put others into bins. Once water is down to eight inches or so, just scoop the fish out and refill the tank. But don't think you're at this point yet, but do consider giving the fish a pH/temperature-adjusted freshwater dip on the way into quarantine if you do end up having to catch it.> Thank you for your help!
<Cheers, J -- >
Surgeonfishes: Tangs for  Marine

Diversity, Selection & Care

New eBook on Amazon: Available here
New Print Book on Create Space: Available here

by Robert (Bob) Fenner
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