Please visit our Sponsors
FAQs on the Powder Blue Tang Nutritional Disease  

FAQs on Powder Blue Tang Disease: PBT Disease 1, PBT Disease 2,
FAQs on Powder Blue Tang Disease by Category: Diagnosis, Environmental, 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

Thin Powder Blue Tang     5/3/13
Hello again crew. Seems like I've been writing you guys a lot lately.
<... w/ too-large image files>
 This will hopefully be my last question for a while! I ordered a Powder Blue Tang online.
<This fish is starving>
 When he arrived he was very thin but he was eating right away. He was even searching for food in the acclimation bucket! He has not come down with crypt and eats voraciously on Nori and Rod's Food soaked in Selcon.
<Ah, good>
 But as stated he is very thin. I am just wondering if there is anything more that I should be doing for him?
<Yes... NLS Spectrum pellets.... Read here: http://www.wetwebmedia.com/pbtfdgfaqs.htm
 Other than supplying him with an endless amount of Nori.
<Very little food value in Porphyra sheets, other algae... Bob Fenner>
 I have attached a few pictures for reference.

Re: Thin Powder Blue Tang     5/3/13
Thanks Bob. Sorry about the image sizes. I can resend with smaller sizes if you would like.
<Ah, no; too late>
 I have various sizes of NL Spectrum Pellets that I can offer.
<Oh, good>
Should I be soaking them in the Selcon solution?
<Maybe for a short while (a minute or two)>
 I am appalled in the condition that this fish showed up in.
<Very common for all wild-caught fishes to not be fed after capture...
through packing, shipping... often even while at wholesale facilities...
And Tangs as you note, eat/forage continuously by day>
 This is the second tang that showed up like this. First one was a Naso that died 4 days after arriving. I could not get that one to eat. Needless to say I will not be ordering from that company in the future.
<Ah yes; good point... Dr.s Foster and Smith (through Quality Marine) is a valid source>
<Welcome, and thank you. BobF>

Powder Blue Tang question   1/29/13
Hello WWM,
I've had a large (4.5 inches)
<Mmm, no; medium. Gets about twice this length>
Powder Blue Tang for the past 8 weeks in my 180 gallon FOWLR.  The tang eats well, on a diet of Spirulina brine shrimp, mussel meat, formula 1, and daily Nori sheets.  His stomach is not pinched in (indeed he has a little belly on him) and he is not thin behind the eyes (per your article) but I can see his spinal column quite easily, especially on the anterior half of the fish. 
<Then is thin... not atypical; and can be fattened up >
The tang is quite active and behaves normally, but should I be worried about this?
<Mmm, no. I'd use Spectrum pelleted as a basic/staple... a few times daily.
Will be plump in a few weeks to months>
  I know tangs have laterally compressed bodies, but I wondered if this was normal.
<Easily starved in transit from the wild, through the chain of custody...
Bob Fenner>

Help! Powder blue tang stopped eating 12/24/10
<Happy Xmas eve>
I have a powder blue tang in a 180 gallon tank that stopped eating and swims at the bottom of the tank like he cannot see.
<Perhaps s/he cannot>
He is bumping into the glass tank and the rocks. He is not very active at all. Water and tank quality is the same and no changes. I am not sure what to do. He does not have any signs of disease on the outside.
<Most often such cases/symptoms point to long/er term avitaminoses... deficiencies in diet... To some extent correctable at times...>
I checked the body and eyes and they appear clear. I do not know what to do. We have had the Tang for about 9 years now and do not want to lose him. Please help.
<Put the two words "Tang blindness" in the search tool here:
and read the cached views. Perhaps addition of supplements to the water, foods will rectify the situation. Bob Fenner>
Re: Help! Powder blue tang stopped eating 12/24/10
Thanks Bob. I will search the site as suggested but I am very concern that he is not eating.
How do I get him to eat?
<Please read where you were referred to. All I know re this issue is archived there. BobF>

Help with a new powder blue tang, hlth. mostly 7/28/10
Dear Wet Web Media staff,
First off, let me just say that your web site has been such a help with both the setting up of my freshwater tank and now my new reef tank.
Yesterday, I went to my LFS and bought a Powder blue tang semi- impulsively.( I knew a lot about tangs and knew my 120 gallon fish tank could support it, but I got home and read that they need an older aquarium.) I tried to return it to the fish store but they would not take it back because it would be too stressful for the fish understandably.
<Bogus, would not be any more stressful than being added to any other tank.>
My tank was cycled with 50lbs of live rock for 2 to 3 weeks. My question is what is and what are the signs of the white stress bar and does he have a chance that he will live.
<Certainly he has a chance of living if properly cared for, not sure what you are asking about the signs of the white stress bar. These tangs do display a white bar in response to some stress, but in and of itself it is not harmful.>
I feed him algae, brine shrimp and New life spectrum optimum salt H20 with garlic in them.
<Lose the brine and garlic, feed occasionally with Mysid but mostly algae is what this fish needs. Selcon or similar additive may be beneficial.>
He looked very healthy in the store.( he is the right colored blue, clear eyes, responsive, active, and eating already.) The only thing I saw wrong was one dark splotch on him but it is already half gone.
I put him directly in my main tank because it was empty and am currently putting stress zyme in that replaces his mucous coat and treating him precautionarily with reef safe kick Ick.
<I would not be using either of these products at this point, unnecessary and if Ich becomes apparent I would go with a more effective treatment method.>
I also gave him a 17 minute freshwater bath and didn't see anything come off of him. Thank you for your time
<Enjoy the new fish.>

Powder blue problems 2/16/08 Hi Bob, <Sam> Sorry to bother you but my powder blue tang appears to have gone temporarily blind I have had him for around 2-3 years. I have always fed him ocean nutrition flakes and occasionally mysis, plankton and frozen marine mixes. He ate some mysis and plankton a few days ago. But over the last week he has stopped eating and on further inspection appears blind. He seems to be swimming in circles. Normally he sits in his hole and comes out at feeding time. Apart from that he is quite a fat specimen. His eyes appear vaguely cloudy and his eye balls are moving a lot somewhat like a toy doll. He can see, but only things that are close to him. I have placed him in my hospital tank with aquabee 200/1 skimmer, eheim wet and dry filter. i have lowered the SG to around 1.018 and added ParaGuard. Do you think he will regain his vision? Regards Sam <I do hope so. As marine fishes "drink" their environment, I encourage you to supplement the system water with a vitamin and HUFA prep... Like Selcon, Microvit... This addition may well serve to reverse some sort of deficiency syndrome in effect here. Bob Fenner>

He Has The Powder Blues (Possible Sick Powder Blue Tang) Greetings,   <Hi there! Scott F. here with you!> Great site!  I learn something new everyday thanks to you folks. <And we, in turn- learn something new everyday from our readers! What a great arrangement!> I purchased a Power Blue Tang from my LFS 2 weeks ago.  I asked the store if it had been eating and they didn't know.  (not a good sign I know). <A good idea is to ask them to feed the fish in your presence. That may at least give you some hint of who the fish is doing; it will also give you a really good hint at how your store works with customers!> This fish is reasonably hard to find in my area so I took a chance.  I left it at the store until they could confirm that he was eating regularly.   <Ah.. good. Glad to hear that!> They did a freshwater dip which is part of their normal process when they get new fish. <Above average husbandry for a store!> After about a week, he has had great color and looked good.  Swimming normal etc. I took it home and put it in my refugium.  I figured if the fish was having any trouble eating, my refugium full of algae would help. <Good thought, but keeping the fish in a separate quarantine tank is a better way to go. By its very nature, a refugium is connected to your main system, meaning a fish with potentially contagious pathogens is exposed to the rest of your population! Better approach would have been to harvest macroalgae from your refugium to feed the Tang while it was in quarantine. Do consider this process next time, okay?> It at more or less right away and started to clean out all my macro algae.  No signs of Ich or any other visible parasites.  After 5 days the fish was good and fat with algae.  And it was definitely coming out just about as fast as it was going in.  :-) <Always a good sign!> This evening I came home from work and the fish was in trouble.  Breathing rate has doubled, and the fish looks paralyzed. It can move it's eyes, and mouth.  It nips at anything I put near it's mouth. The top yellow fin looks like color is flaking off.  There is no sign of anything on the surface of the fish.  The color is very bright.  The yellow is looking a bit "dirty" but still bright.  Any Ideas?  Is there anything I can do to help it out?  What could the cause be?  Water specs seem ok. NH3,NO2,NO3 all zero or immeasurable.  PH is about 8.2,  SG is 1.024 temp is 79ish.   <Hard to be 100% certain, but the potential is there for this to be some sort of parasitic infection. With your good quality environmental parameters, I suppose that we can just about eliminate environmental lapses as a possibility. Another possibility might be some sort of ingested toxin, but I think that unlikely. Rapid breathing, relative inactivity, and color changes are potential cues of further problems.> I moved the fish out of the system and into QT with a bit of copper in it.  Thanks for your help. Brian P-  Cleveland <Well, Brian- I think that getting the fish into a separate tank for observation and/or treatment was a good idea. Copper may or may not be necessary, depending upon what the problem is. If your hunch is that you are dealing with a possible parasitic infection (a common "suspect" with these fishes, particularly with their well-deserved reputation as "ich magnets"), then copper is a good choice. However, be sure to follow manufacturer's recommendations to the letter concerning concentration and duration of treatment. Testing when using copper is essential. Long-term exposure to copper is detrimental to tangs, so if you are using this medication, use it only long enough to affect a cure (again, following manufacturer's recommendations). Formalin-based medications are also good, with the above caveats, of course. Keep a sharp eye on this fish, make sure that he eats. Keep the water quality high in the treatment tank. Also, I'd be remiss if I didn't caution you to observe the display tank population carefully for possible disease signs in the next few days. Stay on top of things, take needed actions as required, and act decisively. You're gonna beat this thing! Good luck! Regards, Scott F.>

Powder Blue Tang Blues  8/30/05 Hello crew, <Larry> As always, thanks for the great website and all of the help you provide.  I find myself in a quandary and would appreciate an outside opinion. <Okay> I purchased a powder blue tang, knowing the poor success record, but having a good tank for it.  I am planning on introducing him to my 240 gallon reef tank with an additional 100 gallon sump housing a macro algae refugium.  The tang has been in a 20 gallon quarantine for 16 days.   <Good> I did make the mistake of cleaning the quarantine tank too thoroughly before introducing the tang.  I initiated a mini-cycle, but quickly got through it by adding some spare live rock to the quarantine and doing daily 25% water changes from the reef tank until the parameters settled (ammonia, nitrites at 0, nitrates undetectable on my kit, specific gravity 1.024, temp 79 degrees).  The water has been stable for about a week and I have cut back to 25% water changes every third day. For the last three days, the tang has been losing weight and it's color is fading.  It does eat the food I've offered (frozen Mysis, frozen blood worms, Caulerpa racemosa (not much eaten), another Caulerpa (I forget which one).  It does not seem interested in Nori I've put in the tank.  While it eats all of this, it would seem that it is not eating enough or getting the correct nutrients.   <Mmm, may be time to dip/bath this specimen and place it... if it continues to lose weight, to lace its favorite food/s with Metronidazole/Flagyl> My quandary is should I abbreviate the quarantine and risk bringing harm to the other fish in my tank or wait it out in the 20 gallon where the tang is obviously not thriving? <Your call... I would move it if it looks "that bad"> I think the tang has a much better chance of success in the reef, but am hesitant to make the switch.  He shows no other signs of disease or parasites.   Thanks in advance for the help, I anxiously await your thoughts. Larry <Bob Fenner>

Powder-Blue Tang Health Hello Bob- Thanks for your time and help. I have a powder blue tang who is eating quite well. I feed him brine shrimp plus, formula two, romaine lettuce, and dried algae. <Both the Nori and Formula II are good foods, but the brine shrimp and romaine are of little value.> His body is very thin (always has been) but his stomach is growing in size in that it is bulging out. It is also very lumpy looking. Should I feed a vitamin supplement? <Yes, I like Boyd's Vita-Chem and American Marine Selcon.> What could this be? <It sounds like extreme weight loss.> Is it just malnutrition and will it heal over time? <If you can get enough of the proper foods into it.> I have only had him for about 3 months. Will he eventually fatten up? I can see his ribs and spine. Could he have an intestinal parasite? <Possible> Thank you very much, Josh <You are welcome. -Steven Pro>

PB tang- swim bladder? Dear Bob I've had my powder blue tang for almost a year. He has doubled in size since I got him and seemed to be the picture of health, his color during the day is a beautiful powder purple rather than light blue. About a month ago, I noticed that his belly seems swollen and he swims in a sort of bobbing motion. He eats standing on his head and I've seen him swim on his side. Since he appears to fart a lot, I assumed he was eating too much. <Or isn't able to "use" (process, absorb) what it is ingesting> I feed green, brown and red Seaweed Selects always soaked in Selcon every day. Also Formula 2, red Tang Heaven and fresh wakame several times a week. <Sounds good, even yummy> I'm suspecting a swim bladder problem. Even though his belly is swollen, his scales are normal, so I don't think he has Ascites... yet. <Ah, a descriptive term... not a "disease" per se... the result of something else> Is there something I can do in addition to soaking the food in Selcon and Zoe? Are antibiotics in order and will he need to be isolated? <I would not isolate this specimen... doubt if this situation is indicative of anything "catching" or that the move would improve its chances for getting better... would cut back on the amounts of feeding though, and only soak food once a week for a while> I'm leaving on vacation Thursday, so any treatment will have to be delayed ten days. Thanks, Linda <The ten days may be what this specimen needs to cure itself. Bob Fenner>

Very Thin PBT - What to do?  >Hi Marina,  >>Hi Tyler.  >It's me again. Just curious if you had found out anything on his swollen stomach.  >>Well, I've gotten some ideas, but nothing concrete.  >I wanted to clear up a couple of things as well. He is always swimming around and grazing on rockwork.  >>Alright, so I believe we can rule out stress, as long as he's not "pacing" the tank. What we're looking for is natural behavior here. However, should you decide to treat him for internal parasites, you MUST put him into a hospital tank to do this.  >He likes to sit up by the powerhead at night after he is fed. He is eating Nori more aggressively and is always alert. He does look like he is putting some weight on.  >>EXCELLENT! I am very happy to hear this, Tyler.  >How long does it usually take fish to die from cyanide poisoning?  >>There are so many variables that I can only give you a broad range, which is from instantly (moot), to about 4-6 months depending on species. I believe this is a high-calorie requiring fish, given its natural diet and swimming behavior/activity level. So, *if* the problem is cyanide, I wouldn't give him more than three months from collection.  >Can they recover from this in anyway?  >>No, the damage is permanent. To the reef from which they're collected as well.  >Thanks.  >>Alright, I'm going to relay portions of Anthony's response to you first: first, in regards to behavior - "...this fish comes from very high action/dynamic areas of a reef (surge) and as such is more sensitive (read: shows stress earlier/first than other fishes). <snip> ...of the fish hanging out near the power head(s). <snip> ...a very typical behavior (stress induced) of Powder Blue tangs in captivity along with "pacing" (running back and forth along the glass as if in pursuit of its own reflection). For reasons not entirely clear to us, the behavior stops with the addition of much better/higher water flow."  >>In regards to treatment and diet - "a preventative flush for parasites would not be bad at all. Seachem sells Metronidazole in a powder form (tube) that can be added to food or water. Not a bad idea here. <snip> ... this fishy needs some fatty and high protein foods. Short and sweet solution would be to get the fish eating frozen Mysis and freeze dried anything soaked in Selco or Selcon. Judging by the glimpse of corals in the background of the picture, it seems like this chap has enough connections to get some Gracilaria from a local merchant or direct them to IPSF.com for "tang heaven". I strongly encourage anyone desirous of keeping a PBT to grow their own Gracilaria in a refugium."  >>Now, Scott Fellman brings up an important observation regarding white, stringy feces; this is a strong indication of bacterial infection. This could be secondary. If this fish has those feces, then an antibiotic (after trying the anti-parasitic meds) would definitely be in order here. As to the swollen belly, it very well could be that it appears so abnormal because this fish is essentially badly starved - as in concentration camp starved. The second pic you sent he does look fatter, let's keep that trend going! Marina

Very Thin Powder Blue Tang  >>Hi, this is Marina again. I had to respond to you ASAP because I took a look at your tang and he is painfully thin.  >Here is my PBT. Does he look skinny to you?  >>As above, painfully so, this fish appears to be entirely unhealthy I'm afraid.  >Like I said, he eats Mysis like a pig and is eating Nori. Should I be concerned? Thanks.  >>There could be a couple of things going on with this fish, both mean that he may eat a large amount, but simply cannot process what's taken in. Parasitic infection (internal) is one, and another, more common unfortunately, is exposure to cyanide. Parasitic infection is treatable, cyanide exposure is not. Feed the heck out of this fish, and read up on Acanthurus leucosternon here: http://www.wetwebmedia.com/powdbluetg.htm   (Although as time goes on, more and more people are having good success with these fish.) Marina

Very Thin Powder Blue Tang - Follow up  >Thanks for the quick reply.  >>You're welcome, I feel the fish looks bad enough that it was warranted.  >I will start feeding him as many times a day as he will eat. Should I try foods high in protein?  >>I wouldn't target in that manner, what's most healthy is as much variety as he will take. Along with (or in lieu of) that, soaking in the supplement, Selcon, will help greatly. He definitely needs vegetable matter, so if he doesn't take the Nori, try romaine lettuce, "nuked" broccoli (soften the flesh for the fish), spinach, "nuked" kale/Swiss chard, zucchini.  >What symptoms are related to internal parasites?  >>What you're looking at and describing fits BOTH internal parasites and cyanide exposure results. If you've had the animal for 6 months or less, then it makes the cyanide exposure more of a possibility. Do Google our homepage for "internal parasites", just in case, but I wouldn't treat him at this point, he's far too thin in my opinion to handle the strong medications.  >All my other fish seem fine. Thanks.  >>Good, glad to hear that. It may be that he's had a very rough go of it, these fish ARE delicate. Hopefully your set up is such that he's got the best chance of recovering, or at least putting some weight on. If you check today's daily picture, I specifically posted a healthy PBT for you to see what they should look like, and I specifically chose an aquarium specimen, for comparison. Best of luck! Marina
Very Thin Powder Blue Tang - Follow up 
>Do I ever appreciate the advice.  >>I'm glad to help.  >Today, he ate Special Formula VHO.  >>EXCELLENT!  >I will try different foods each day. Just to let you know, because I never said, my tank is a 135 reef with more than enough rockwork to graze on. Thanks and I'll keep you updated.  >>Then I think we'd be hard-pressed to find this fish a better place, yeah? I'm keeping my fingers crossed! Marina
Opie, the Skinniest Powder Blue Tang - Part IV 
>Thanks for all the responses, it is very much appreciated.  >>You're quite welcome, Tyler.  >I don't think water flow is an issue, since I have four MaxiJet 1200 powerheads in the tank along with the spray bar returning the water from the sump.  >>Honestly, considering the areas where this fish is found, it's difficult for the home aquarist to duplicate the heavy movement found in these frontal reef zones. Closest I've seen is one of the LBAOP's California displays, and what they have is a HUGE (and loud) surge-bucket setup. The water movement in that display is TREMENDOUS considering the relative size. (And boy did it get a little bit scary a couple of times feeding, the rocks you have to step onto can be quite slippery!)  >One more question & I will leave you alone.  >>No no, please don't. We're all interested in this fish's progress, Tyler.  >Would you recommend feeding him with the Metronidazole in the display or in a QT? I did a search and got mixed answers. Thanks for all the help.  >>Absolutely always do any and all treatment in quarantine/hospital tank. Marina

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
Become a Sponsor Features:
Daily FAQs FW Daily FAQs SW Pix of the Day FW Pix of the Day New On WWM
Helpful Links Hobbyist Forum Calendars Admin Index Cover Images
Featured Sponsors: