Two more questions. Orange Shoulder Tang beh., Chrysurus A HLLE?  11/25/2007
Thanks again Bob.
<Welcome Steven>
Two more questions and then I won't bother you (at least for a while).
I have two fish that I wanted your opinion on their coloration. First I have a Orange Shoulder tang that I bought about 1 1/2 years ago that was / is a juvenile about 3.5" long.
<Neat animals>
He has grown maybe to 4" but is still yellow. He has the outline where the orange oval will appear but that is about it...no signs of wanting to change and doesn't grow very fast. How long would you guess until he begins his adult color change?
<A bit longer... perhaps a half to a full year. This fish is right about where such changes occur size-wise. Am in the process of sorting some of the genus Acanthurus tangs FAQs, including this one... and am out in HI currently... where most of this species are collected for the trade>
Second question is I have a Chrysurus (sp?) angel and have had him for about 1 year. He is approximately 5" long and has recently started to turn color around his mask (head area). At first I thought it was some sort of fungus, but have seen a few photos on the web and have seen the exact same marking, but these photos also only show the head area to have this coloration. Will he change completely or will this be the extent of it?
<Only time can tell here>
It kind of doesn't look as pretty as he did before this change, but if the entire body turned this kind of yellow/tan color it would look nice.
<There often is a bit of lightness, a sort of mask with this change... I do want you to consider the possibility that this might be HLLE... Please read here: http://wetwebmedia.com/hllefaqs3.htm
and the linked FAQs files above. Bob Fenner>
Your input is greatly appreciated.
Thanks,
Steven

Clown Tang Aggression…Fueled By The Lunar Cycle? - 09/29/07
Here is my dilemma, I have a Clown Tang about 6-inches, and every few weeks he acts very weird.
<<A very aggressive (even “mean”) species>>
About two months ago he tried to kill my Purple Tang (luckily I got the purple out in time but he had 4 cuts about half an inch long and put him into another tank).
<<Likely the two are together in a “too small” environment>>
This month he has been fighting his reflection in the glass for the past 3 days.
<<Typical behavior for most any territorial species>>
My tank is a 125 with a 55-gallon sump and 200 LB of live rock, chemicals are all good.
<<Mmm, yes…and too small to be mixing this large (can exceed 16” in the wild), very active (likes LOTS of open space), and very aggressive fish (did I mention “mean?”) with other Tang species>>
I was curious if the Full Moon cycle could up his aggression?
<<Honestly, I can’t say for sure… But, if you’re not running some type of controller/gear to replicate the Lunar Cycle how does the fish know? Or maybe…the fish senses/feels a change in gravitational forces…>>
Because I found that most tangs breed in the wild by Full Moon, or New Moon. When it first got really aggressive was a Full Moon and this time the Full Moon just past. Thanks for your input.
Kevin
<<The Lunar Cycle may well induce a neurochemical change increasing aggression in this very aggressive species (is thought to happen to humans too)…which is already exacerbated by the confines of the tank and too much rock/not enough open swimming space for the Tang’s liking. Regards, EricR>>

Atlantic Blue Tang, beh.    8/8/07
Hello, all...
I wrote shortly ago regarding the possibility of purchasing a Sargassum Trigger... However, due to the possibility of incompatibility with my shark and puffer, I opted instead for an Atlantic Blue Tang, a gorgeous fish about 5" long. I was real fortunate to be able to purchase him from a very small LFS that had the fish alone in a tank on it's own system for a couple of weeks.
There was a short piece on wwm about him under the ID section, mentioning it's one of the 'good' tangs. I read most of the FAQ (I think) about this fish, as well. My question is more about the demeanor of this fish, it is thick and healthy but is terribly shy, staying underneath live rock constantly if I'm near the tank.
<Is a social species... living in sometimes very large groups... in open spaces...>
I can back away and peak around the corner after a while and he will be out. I believe he has eaten Caulerpa (sp) algae that I put in there, and I would imagine he picks at the live rock, but is too timid to come out when I am feeding everyone else, so I doubt he has eaten yet.
<... your system is too small, too crowded... We've been over this...>
Might you have any specifics on this fish other than what is written in the ID section? There's not much in FAQ about this specific tang, and I'm wondering if they take longer to get comfortable, if they browse after dark (which seems to be when all my fish eat algae), and your opinions in general on this gorgeous fish.
Bob, on a side note, after performing another large water change (prior to this purchase, I might add!) and adding a bit more carbon, the shark behavior has gotten much better.
<Ah, good>
I think there may have been some quinine left in the system, and as the carbon removed it he returned to normal activity.
Once again, thanks so much,
Thomas
P.S. Have you ever seen a dogface puffer that loves algae
sheets? It seems I have one...
<Oh yes. BobF>

Re: Atlantic Blue Tang  8/9/07
Bob, you think even the 200 gallon is too small? If you think so, I'll scale back. Thanks!
<I think with what you've listed... sharks, puffer... that you're more than topped off. RMF>

Mimic Tang Behaviour  3/19/07
Hello - First off, thank you for providing such a great site.  I often  have questions and find the answers just by browsing around.
<Yes... and thank goodness... there are tens of thousands of unique ISPs here every day...>
  But this is  one I couldn't find.  I have a 75 gal tank that has only been up and  running for about 4 months.  So far so good.  I have 2 clowns (percula  and Clarks) and a yellow mimic tang.  Just in the last few days, my mimic  tang has been rubbing his side against the sand?
<Not an unnatural behavior... and not to worry unless this becomes "excessive">
It is very brief, quick  movement and then he is back to swimming as usual.  He is just doing it  every now and then and not constant, but I have seen it happen at least 4 times  today that I have noticed so I assume he is doing it more.  Is this  something I should be concerned about?  
<Not really>
I am hoping it isn't any kind of  skin condition or whatever.  He is showing a little bit of aggression to one  of my clowns, but that is only when the mimic tang feels the need to invade the  clowns space around and underneath our BTA.
<Also to be expected for the species, genus>
Other than that, they get  along.  Thanks for your thoughts on this.  
Hoping it is just a little  quirk of the mimic tang, and not a problem - Stacy
<No worries. Bob Fenner>

Sohal Sand Slap 12/15/06
Hi There!
<Hello Heather...Always liked that name.>
I have a behavioral question about my Sohal Tang.  He? is housed in our 240 gal. reef tank that is aquascaped with many caves, caverns and tunnels.  He races through the tank when not constantly grazing on our rock or supply of Caulerpa <caulerpa>. He is wonderful to observe; but his one behavior puzzles me.  He will zoom through the tank, dive to the bottom and slide sideways on the stretch of sand bed that does not have rocks on it slapping the sand with his tail. Sometimes he will take the side of his face and do the same thing.
His tank mates include a Naso Tang, Hippo, and Yellow Tang (who unbelievably rules the tank at this point -reminds me of a mother trying to control unruly kids - we put her in first) 2 clarkii's with Anenome.
All mates are equally spirited towards another, no cowards or bothersome aggression as each have claimed their own space and have seemed to create a community space in the middle rock area of the tank where the cleaner shrimp has set up his services.
<The benefits of a large tank.>
We know the Sohal is the bad boy of the tang group, is he just showing off?
<Sand slapping is generally a sign of an oncoming parasitic infection.  <<And aggression. RMF>> Never saw one doing this to show off, but have seen tangs do this on occasion but not on a continual basis.  Have you quarantined this fish before placing in the show tank?  Hopefully so.>
My sweet Naso appears that she is trying to learn how to do the sand slap - I think she is too much of a lady to exhibit such behavior though!  Any experience with this?
Amused and Puzzled,
<I'd keep a close eye on your Sohal for signs of disease.  James (Salty Dog)>
Heather

Acanthurus olivaceus pooping behavior, BGA control 10/30/05
Steve here.
<Bob here, HI and Hi>
Hope this email finds you well.
<Yes, thanks>
A couple of questions: I have a Juvenile Orange shoulder Tang around 3.5" long and have had him a few months now. He acclimated very well and getting along with his mates. He eats well, grazing off of 250 lbs. of live rock, Nori on a clip, and variations of Omega Flake food, Ocean Nutrition Pellet w/ garlic, frozen cube, etc.
<We're out diving with this species most days>
My question is that when he "poops" a steam of what looks like sand comes out.
<Good observation>
It almost looks like my very fine live aragonite sand that is in the deep sand bed. He picks and feeds off of the sand bed along with grazing off of the live rock. I can see his ribs, but I think I read on your site that it was not uncommon amongst Tangs.  
<Correct... they do ingest bits of substrate... sort of helps... like some birds' crops... with tritiation/chewing...>
Second question: I wrote recently about a fight with Red Cyano that has been forming on the sand bed. I physically remove it (siphon) and have performed weekly 10% water changes, watching that I don't feed more than the fish can eat and not adding any other nutrients to the tank. The tank is 215 gallons, 50 gallon wet/dry, refugium with Caulerpa, 250# of Tonga live rock and the water parameters are fine, ammonia 0, nitrite 0, nitrates 10 ppm, salinity 1.024, water temp 80.5 - 81.5 F. I have ready on your site that treating chemically is not advised, so I have been doing all of the things this site recommends like clock work for two weeks and if anything it has gotten a little worse.
<Mmm, you might want to consider modifying that wet-dry, switching to another genera/species of macroalgae... perhaps improving your skimmer/skimming...>
I put a sock of Phosphate granules, increased aeration, cut down on nutrients, and performing water changes weekly (at
least 10%). My Ph has remained stable at 8.3. Please let me know if I am missing anything, or should I be looking at something like Chemi Clean (by Boyd)? I don't want to add anything that will kill my live rock, or good bacteria and I suspect that anything that will kill Cyano bacteria may do so.
Thanks for your words of wisdom.
Steven
<Don't know re wisdom... but do take a read (again?) through the WWM files on Cyano... not hard to control once you know how. Bob Fenner> 

Indian Ocean Mimic Tang
Hi,
<Hello there>
I recently bought an Indian ocean mimic tang and it is in my QT with 2 common clowns  and a six line wrasse. It has 0.4 mg/l of copper in the form Seachem Cupramine. I plan to keep them there for at least 30 days.
<Copper is hard on Tangs>
The other three side of the tank is covered with a blue backing and is lighted by a small lamp. The problem is that the tang is swimming frantically along the front of the QT. When I go near and stick a finger at it (in front of the glass) he will swim back and hide behind a plastic pot. Within a second he is back out swimming frantically.
<Likely in reaction to its own reflection...>
The clowns seem kind of stress by his behaviour and appears to be hosting the flower pot. They used to be swimming around everywhere before  the tang was introduced.
Is there anyway to explain this behaviour? Is it normal?
<This animal is probably seeing its own likeness... you might try decreasing the light inside the QT tank, or covering the outside/last panel... Bob Fenner>
Thanks.
Chee Thong

Tangs Fighting
Hi Bob it's Carmen from Cleve again.
<Hi, You've got MikeD here today>
Just wondering if you could give me some advice.<I can try>
I bought 3 small regal tangs about 6months ago. They all got on really well as they were slightly different sizes. But now as they are bigger the smaller one is fine, he just leaves the area if the bigger ones go near him, however the other two bigger ones are similar size now and they constantly bicker and chase each other.<This is actually normal, and the reason most books suggest one per tank> Their fins are slightly tattered and they now have small scratches on their bodies from fighting amongst the rocks. Their coloration has faded slightly compared to the smaller more peaceful one. I know this is territorial behaviour, but I was just wondering if this will continue or will they eventually work out their disputes.<Often the dispute ends with one fish left alive> Should I remove
one?<I'd remove TWO> But then they will just start on the smaller one, wont they???<Yes, Ma'am, eventually>
What do you suggest. There are plenty of other areas that they could go hang out, however they keep fighting over the same rock, where they did once just all sleep peacefully in.<What you see in a sale tank or a huge tank is one thing, but the books are pretty specific about one per tank as they grow larger. This is why.>
Thanks, waiting your reply.<Sorry it isn't the one you wanted. Good Luck!>
Carmen

Clown tang
Bob,
Its been 3 days now, and my 9 inch clown tang's spines are still stuck out. I noticed that all of the other fish are terrorized, and scared to come out.
<I would be too.>
They were never like that before. The clown tang thinks he's the boss or something. 
<He IS>
Checking any fish that dares to come out. Will the spines ever go back in?? Can I do anything to help him put back his spines???
<Perhaps placing it in a much larger, already established (pecking order with large livestock) system... Otherwise I'd trade this bad boy in. Bob Fenner>
Linstun

Re: clown tang
Bob,
I wouldn't trade this guy for no one. I got this clown tang from the marine center. Its an African clown tang. Plus they are super rare, most of them die anyways. But not mine. Anyhow there is absolutely no way that I can catch him. even to move him to another system. You see I don't want to damage his spines. Plus there sticking out. If his spines were to get pulled off, I'm
sure they wouldn't grow back. Plus he would probably die. 
<Actually... we cut (not pull out entirely) these spines in catching, moving wild tangs (to prevent damage to nets, bags, other fishes, divers...)>
I remembered on your last response that you saw some clown tangs that errantly had their
spines stuck out, and they never folded back. Is that true?
<Yes, so. Bob Fenner>
Thanks, Linstun

Re: clown tang
<PRE>so they do grow back like finger nails??
<Yes. Bob Fenner>

Achilles tang
Hi Bob,
I read your section on Tangs and was interested in knowing a little more about the Achilles tang. Would
an Achilles tang do well in a 70 gallon fish only tank with a lot of water circulation and would it be the
most dominant (tankmates Blue Angelfish, arc-eye hawkfish, orange Anthias)? Thank you for your time.
Sam
<Only experience can tell, per specimen... try to secure one that is "fresh" from the wild, rather than one that has been languishing between there and your source for weeks... do definitely freshwater dip and quarantine the new arrival for two weeks ahead of placing in your main system... provide some sort of biological cleaner... and keep your eye on it henceforth... for parasite problems... as they will arise first with this fish. A seventy is small for this fish alone, let alone with an large angelfish species... Bob Fenner>

Clown Tang
Hello there Bob: have a question:
I just bought a clown tang. This will be the first and last time I buy a fish without doing research on it first! I've been fooled or suckered by the pet store!! See, The pet store told me it was just as hardy as my yellow tang!! After doing research on the clown tang I just bought, I am finding from most of the sources that it is a difficult fish to maintain. Just exactly how difficult is this particular fish? 
<Not so much as a juvenile, let's say under four inches total length, but as they get larger... can become trouble behaviorally... beating up on other fishes>
It gets along well with my yellow tang and all the other fish in the tank. How sensitive is this species? 
<About a "four out of ten">
I've got a 75 gallon tank with plenty of live rock and plenty of hiding places. I am pretty anal about doing a water change every month. I must admit that I don't pay crucial attention to my water chemistry. I haven't had too many diseases yet. Only my yellow tang has had a bacterial infection once (fin rot). I have a wet/dry filter, protein skimmer, and a canister filter. 1 48" actinic light, 1 48" full spectrum light, and a 6" compact florescent light (with 2 bulbs). I only have a year experience with salt water tanks (16 years freshwater). Would it help if I told you I was a biology major?
<All understanding "helps">
(meaning I'm familiar with chemistry, etc.). well, let me know what I should do.
Thank you very much
Jennifer Minnick Logan, Utah
<At this point, just keep an eye on the specimen. If it becomes overly aggressive, have a stand-by plan for its removal. Bob Fenner>

Bob please take a look, Clown Tang... some differences of experience, opinion
Hello:
I am a biologist, specializing in habitat re-creation. All Tangs school, but not year-round. 
<Agreed, and some species, localities far more than others>
The Clown Tang schools year-round and is one of the few Tangs that breeds gregariously. 
<Acanthurus lineatus? Does not school often at any of a few dozen places I have photographed and collected them. It is almost always found singly, I assure you>
According to my sources at the American Marinelife Alliance, only Tangs caught in the Philippines are usually drug-caught, and also from the Fiji Islands
<What? Tangs are not targeted for the ornamental industry in Fiji by and large... and no fishes are captured there by anything other than fence and hand net techniques... In the Philippines, Acanthuroids are rarely taken with cyanide... again, I lived there and have visited on many occasions... other fishes are captured with poisons however>
and the Clown Tang is rare in those waters. Call your local public aquarium, and ask them about their
record of success. Bet you'll find they have a hard time with them too.
<Don't know what you're referring to by a hard time... historic survival rates? I am sure you are right if this is what you mean... this species, A. lineatus does not fare well in captivity>
I worked at the New England aquarium as a Grad student for a few years as part of my R.A. program at U.R.I. They couldn't keep them alive under absolutely perfect conditions in schools of 6 or more. The only way they kept them alive was to increase school size to more than 20. 
<Interesting. About what size individuals were involved? Can you tell me where these originated?>
Incidentally, almost all Clown Tangs (Acanthurus lineatus), are collected in Micronesian
crystal-clear waters in depths of about 25 feet using nets. They do occur on reef flats and on the SEAWARD reef margin, but do not occur in shallow turbid water that I know of. I have checked six references on this and they all agree that the fish occurs in clear water only above the reef, 
<Agreed. This is overwhelmingly the conditions where I've encountered the species>
though they may also be found in lagoons. All references I found say they require very well-oxygenated clear water.
<Again, agreed>
Like most Tangs, they are rarely caught using sodium cyanide as their skin absorbs the drug directly and damages the sub dermal tissue. Drug-caught Tangs usually die on their way to the wholesalers and never even make it to market. Tangs are easy to catch with nets when they school. One diver guides
the school into seine nets held by another diver. Why use drugs?
<Can't think of many good reasons... am surprised you seem to state that the group IS collected with cyanide, then categorically state why it cannot be so...>
Take it with a grain of salt. If you get one, let me know how you make out.
<With what, a grain of salt? In our stores (gone years back) we rarely offered much of the (if memory serves) of the 32 species of Acanthurus, and almost never, A. lineatus. I don't deal with collecting this species at all, nor keep it in marine aquariums... Bob Fenner>
Dave
Aquariumpros.com