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FAQs about Imperator Angels 1

Related Articles: Imperator Angels, Pomacanthus Angels, Marine Angelfishes

Related FAQs: Emperor Angels 2Emperor Angels 3, Emperor Angel ID, Emperor Behavior, Emperor Compatibility, Emperor Angel Selection, Emperor Angel Systems, Emperor Feeding, Emperor Disease, Marine Angelfishes In General, Angelfish ID, Selection, Behavior, Compatibility, Health, Feeding, Disease,  

An Emperor changing to adult coloration in the Philippines.

Angelfishes for  Marine Aquariums
Diversity, Selection & Care
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by Robert (Bob) Fenner

Imperator angelfish questions Hi.  I two questions.  First, I have an opportunity to purchase a P. Imperator that was collected in or around Japan. The catch is that I will not be able to see the fish before I commit to purchasing it. I know that there are color variations in P. imperator based upon geography and have been told that specimens from Japan are uniquely colored.  The problem is, after combing through books and searching online, I can't find anything that discusses this variant.   Do you know how they are different and/or can you direct me to a picture of one?   <Mmm, no. I have read (fishbase.org among other places) that the species ranges to S. Japan, the Ogasawaras... but have never seen it imported (to the west) from there> This fish would be the only angelfish in a 180 gallon LRFO system.  Finally, I have purchased fish in this manner before and, with rare exception, most all have thrived.  Second question.  I also have the opportunity to purchase a pair of, or at least one, C. interruptus and also one C. Multicolor.  The fish, if I do purchase them, would go into a 110 reef tank that already has a C. aurantius.  I have read the FAQ's on keeping more than one Centropyge per tank and know that generally its a bad idea.  Not wanting to miss out on these rare and beautiful fish I'm trying to cover all my bases before making a decision. I'm wondering if you think that size of my tank would allow me a greater likelihood of keeping an additional Centropyge species and, if so, which between the C. Interruptus and C. Multicolor would be less likely to cause a problem with my C. Aurantius.   <Likely the Interruptus, being a bit smaller... but Goldens are used to a good amount of space to themselves (thousands of gallons in the wild). Bob Fenner> Your help and opinions are much appreciated.  Michael Jacobs

BALANCE OF POWER (Emperor Angel, dominance hierarchies) Morning gentlemen, I've emailed Anthony a couple of times regarding the removal of a yellow tang from my 75. I replaced the tang with a Paddlefin Wrasse which I figured would not fight with my purple. I also have an Emperor who runs the tank. I know I know, I need a bigger tank! I plan on getting one but now it seems I may have to do it much sooner then I thought. Before I had a problem with the two tang fighting. Since I've removed the yellow which I perceived to be the instigator of most of the violence, my tank has become like the wild west!!! My Emperor has become absolutely domineering. He's chasing everything he sees. My tiny jewel damsel is chasing my new wrasse, my new wrasse is about to kill my Luther (?) Goby, and to top it all off my Levi Angel who was eating and PERFECT 2 days ago is dead! I've had marine fish for 2 years now and I still can't figure them out. I had cichlids for about 12 years before I switched and even though they were nasty at least I could predict what they would do. I think my problem is that I'm caught somewhere between a fish only, and wanting some of the cute little reef type fish. That and the fact that my Emperor has become a monster. Well I didn't listen last time, but I'll heed Anthony's advice this time......I'm NOT REPLACING any fish that die or get moved out as a result of this "chemistry" problem. I guess this isn't so much a question as it is a warning to all those who are reading this FAQ. I'm not getting rid of my Emperor, I'd rather have only him, but I will be looking for a bigger tank much sooner then I planned. Realistically guys, how much is a 300gall fish only tank (done right) set up going to set me back? Thanks gents. Rick <Thank you for the ends up/warning to others. As you eluded to, it is sometimes very difficult to predict how certain fish will react in any situation. As far as your 300 gallon tank, it will easily be several thousand dollars, probably a minimum of $3000. A big difference in price will be the choice of material for the tank, acrylic or glass. But expect $3000 to $5000 regardless. -Steven Pro>
BALANCE OF POWER (Anthony's turn)
Morning gentlemen, <for me at least at 2PM...hehe. Anthony Calfo in your service again> I've emailed Anthony a couple of times regarding the removal of a yellow tang from my 75. I replaced the tang with a Paddlefin Wrasse which I figured would not fight with my purple.  <yes... a reasonably safe choice indeed> I also have an Emperor who runs the tank.  <not a surprise... characteristic for the bigger angels on a reef> I know I know, I need a bigger tank!  <I knew I liked you...<G>> I plan on getting one but now it seems I may have to do it much sooner then I thought.  <Ahhh... the fish are forcing the hand. Do they own us or do we own them? I suppose that I don't mind being owned by such beautiful companions. Like Hugh Hefner of the Fish Geeks, I suppose> Before I had a problem with the two tang fighting. Since I've removed the yellow which I perceived to be the instigator of most of the violence, my tank has become like the wild west!!!  <still, it was a good move and likely to have helped. It didn't! But you were correct to play the odds> My Emperor has become absolutely domineering. He's chasing everything he sees. My tiny jewel damsel is chasing my new wrasse,  <that's funny...sort of. Are they named Stan and Ollie?> my new wrasse is about to kill my Luther (?) Goby, and to top it all off my Levi Angel who was eating and PERFECT 2 days ago is dead!  <that's because you jinxed yourself a couple of weeks ago by saying that your dwarf angel was an exception in hanging with the big boys <wink>> I've had marine fish for 2 years now and I still can't figure them out.  <isn't there a joke about women in there somewhere?> I had cichlids for about 12 years before I switched and even though they were nasty at least I could predict what they would do. I think my problem is that I'm caught somewhere between a fish only, and wanting some of the cute little reef type fish.  <a very common situation, my friend. But your fish are VERY fish only/non-reef personnel> That and the fact that my Emperor has become a monster. <but a beautiful monster at that> Well I didn't listen last time, but I'll heed Anthony's advice this time......I'm NOT REPLACING any fish that die or get moved out as a result of this "chemistry" problem. I guess this isn't so much a question as it is a warning to all those who are reading this FAQ. I'm not getting rid of my Emperor, I'd rather have only him,  <very cool... I totally agree and respect you working the tank around its needs> but I will be looking for a bigger tank much sooner then I planned. Realistically guys, how much is a 300gall fish only tank (done right) set up going to set me back? Thanks gents. Rick <a tough estimate to make, depends on regional market, glass vs. acrylic, re-using equipment, etc. But assuming some worst case scenarios, this should still be able to be done for under $2K. If you are a little handy (stand/canopy) and are reusing equipment/live rock... this could really be a lot closer to one thousand bills. Best of luck with the dream tank, bud. Anthony>

Emperor Angel Bob, <Steven Pro this evening.> I have a 6 inch Emperor Angel. I have had him/her for about 2 years now and have never had a problem. Yesterday, I noticed pits in his/her face. They somewhat resemble acne pock marks. I have a professional cleaning service take care of water changes, which I get done once a month, and just had one done last week. They use reverse osm. water. Chemically, the water tests out fine. Do you have any Idea what this could be? Thank you for your help. Doug <Sounds like the beginning of Head & Lateral Line Syndrome/Erosion. You can read more about this here http://www.wetwebmedia.com/hlle.htm -Steven Pro> <Sorry, wrong link the first time. http://www.wetwebmedia.com/hllefaqs.htm -Steven Pro>

Emperor Angel Question Hi Bob, <Steven Pro this afternoon.> I have an 11in. emperor angel (I was told from Christmas Island) that I put in my tank six days ago. Although he is very active, he has not eaten yet. I have tried feeding him a variety of foods (freeze dried krill, frozen krill, silver sides, mussels, squid, and a variety of frozen angel formulas). He seems very shy and does not seem to like it when I try using a feeding stick or my hand. There have been a couple of times where he will approach the food, but will not eat it. None of the other fish are having difficulty eating nor are they pestering the angel in any way. This angel is in a 400 gal tank w/live rock and the water quality is very good (using RO/DO water). I called the store where I got him from and they told me the only thing that he would eat was freeze-dried krill. The store also told me to lower my salinity from 1.022 to 1.016 because that is what it was in the tank they had him in for 5 weeks; should I do this to my tank? I would certainly appreciate any suggestions to get this guy to eat. Thanks so much for all your help. Randy Fontana <Do not mess around with your S.G. The fish has already acclimated to your current conditions and changing things so dramatically will not help him begin to feed. You should try feeding your fish some frozen Mysis shrimp and Nori seaweed. The Angelfish is going to require less meaty foods. A diet rich in plant matter with some sponges mixed in would be better. -Steven Pro>

Stress/Fright Pattern on Emperor Hey Bob (and Co.) <and strange company he keeps, indeed! Anthony Calfo in your service> As I told you last time, my Emperor's white discolorations disappeared after a simple water change and some vitamins in his food. I've only used the vitamins 3 times so I think it's the water change and refreshed carbon that did the trick. I noticed last night he was just starting to get them again. It's been about a week since my last water change so I'll do another tonight. It seems that my Emperors colors are a direct reflection of water quality and that they can change within a day. <precarious water quality if so. Maybe you are short in stature like me and dipping your armpits laced with aluminum infused deodorant is affecting the water quality so...hehe. Just a theory (with some truth in it! regarding toxicity!)> So it seems my water deteriorates to a point where his color is affected in about 6 days. My question is: Is this normal?  <not by any stretch of the imagination> I don't think so. Perhaps I have too much of a biological load on the tank?  <agreed...a very common and likely scenario confirmed with water tests> I'm considering removing one of my large tangs as they seem to produce a massive amount of waste. What do you think is going on here? <agreed on the tang... and also beneficial that the tangs intimidating presence (even if not aggressive) is removed (by virtue of his size if nothing else. Kindly, Anthony> Rick

Stressed Emperor Thanks Anthony. <quite welcome, my friend> I'll get rid of a tang this weekend. One of them does challenge the Emperor once in a while but the Emperor puts him in his place every time.  <yes...but the constant threat and stress to do so takes a toll> The emperor actually makes a LOUD barking sound at the purple tang. <very cool. Hopeful not much longer though <smile> Anthony> Rick

Emperor Angel If you don't mind Anthony, one last follow up. <no trouble at all...it is an honor that anyone should care to know one's opinion> If I hear you, I should get rid of both of my tangs (purple/yellow). <not necessary...but it would be nice. There are much less stressful tankmates> The tank is 75gall. I have no problem moving the tangs as I just love this angel and would be happy with him as the only big fish. <admirable> However, I would like to put something else (smaller obviously) to keep the tank active.  <considering the angels adult size...the next fish will have to be small if you add anything at all in replacement> Any suggestions ( I know you guys don't like to do this) I already have a maroon clown and a Levi Angel. <there are so many choices...but your goal should be to find something that is dissimilar in shape, size, and/or color and most importantly... a different feeding mode. For example, there are a lot of exciting wrasses (like fairies) that are colorful, active and not at all competitive with the angel. Choose carefully...some are incredibly hardy and others near impossible to keep alive. Look through some pictures and follow up with a short list if you want a second opinion> Thanks....for the last time I PROMISE. <no worries at all> Rick...overlooking ground zero in NY. <Ahhh...It actually brought a tear to my eye to watch the Budweiser commercial (during the super bowl) with the Clydesdale horses trekking to NY to bow at the Statue of Liberty...seriously. And I'm not even a beer drinker. Kind regards, Anthony

My Emp. male or female? hi bob, I have a 12 plus. in. Christmas island emperor angel. He's in a 240 gal. tank doing very well. Anyhow my question is . How can I tell if he's a female or male? Oh and another question is. How come at his large size. He doesn't have a streamer on top yet?? I've seen Emp.s half the size of mine with 3 to 4 in . streamers already? Do only males sport streamers?? <As far as I'm aware there is no reliable way to sexually differentiate Pomacanthus imperator externally... Have seen "pairs" in the wild on occasion... w/o visible (to me at least) sexual dimorphic, dichromic differences... Both sexes can bear unpaired fin "streamers" from what I know. Bob Fenner> Thanks, Linstun Lee

Sexing emperor angels bob, I have a huge 13 in. Christmas island Emp. He's thriving in my 240 gal.. How come he doesn't have a streamer at the top end ?? I've seen 5 in. adult Emp.s sport streamers. Do males only have streamers? <Same input/answer. Bob Fenner>

Splotchy white areas. Thanks for the answer yesterday on feeding my Emperor, Well now I have another....sorry. I've had this Emperor for about two weeks now and he's doing great. He eats everything I put in there now and if anything my tangs are now getting the shaft. But there is one last problem....and it may be a bit serious. I HAVE had parasitic infestations in the past as I have bothered you guys about before. Once I got a UV sterilizer I achieved a "detente" as Bob so eloquently put it. My established fish have been spotless since and new additions usually get a little something during the first few weeks and they get through it. Seems the UV sterilizer breaks the cycle so when the parasites drop off they don't usually get a chance to re-infest. Well my Emperor got something.....definitely some ich, and maybe (I pray not) some Oodinium. I say the latter because of a haze he had over his eyes. I said I would never use "Kick Ich" and "Rally" again but I gave one dose of each so he would slough off what was on him and perhaps he wouldn't get reinfected. It seemed to work, but now he has something that I've never seen before. He has many white splotches on him. They don't look like parasites, but more like circles of discoloration. I'll estimate they are 2mm around.  <These markings are very likely from the treatment... and will go away in time... on their own... take care to maintain good water quality, proper mixed nutrition... and all should be fine> He eats like a champ and is the most outgoing fish I have ever owned. He gets red, green, brown algae, formula one, angel formula, and frozen mysids.......he eats better then me!! I fear that I have velvet, although the times that I've seen it, it was never in individual circles like I have it now. I've always seen it as a consistent haze over the fish that ends up killing from the gills on out, not to mention the fish are usually visibly sick which this one is not. Any ideas? Could these be marks from where there "were" parasites? Either way I'm doing a mega water change tomorrow. Thanks for more of your time gentlemen....I look forward to your reply. <Patience my friend. Keep your eyes on the prize. Bob Fenner>

Emperors new clothes No question today Bob, just an update. Regarding the "white circles of discoloration" on my otherwise healthy Emperor: They're gone! All I did was a water change and refreshed my carbon. I also started adding vitamins to my frozen food. 2 days later........he's as perfect as he was the day I got him. In fact, he may be better. My purple tang tried to challenge him yesterday and the Emperor was barking at him!!! It was quite loud and quite amazing. Actually I heard they rub 2 bones in their head together, but whatever it was it worked. He is the king of the tank still. Thanks for your help..........Rick NY <Ah, thought as much would happen. Glad to read of your success. Bob Fenner>
By the way
Just read one part of your site that I never go to before: Your credentials!! Thanks for taking the time to answer our little questions Bob. Rick. NY <You're welcome my friend. Bob Fenner>

Re: EMPEROR Thanks Bob Turn's out last night I figured out how to feed him anyway. I just put it right in his mouth! He comes to the top and takes it right out of my hand. I also noticed another more serious problem last night that I knew would appear. I emailed you a long time ago and told you that with my UV sterilizer I felt I had "won" the battle. You told me to call it more of a "detente". You were right. All my est. fish have been clean ever since but new additions usually end up with a few parasites for the first 2 weeks. Nothing compared to the way it was before the UV though and once they are clean they usually stay that way. Well last night I noticed my new emperor had a bunch on his eyes and elsewhere. Hopefully now that he is eating a full and diverse diet every day he will get through this period. If he doesn't I may have to go out and drink something! <A good idea all the way around. Relax my friend. Bob Fenner>

Shy Emperor Angel and Fishing Hooks Hey Bob, Quick question about an Emperor that I just bought. <Anthony Calfo in your service while Bob sits staring at his hand... "all natural" acid flashback, I think> First of all it was at the store for about 2 months and ate out of my hand there.  The transition to my home was so smooth because he just went into a bucket <grumble, grumble... buckets are very hard on fish eyes/membranes... a bad way to ship. Soft plastic bags flex. LFS boo-boo> and into my tank without a net. <excellent and considerate!> 5min after being in the tank he was approaching the top when I came to the tank.  He is PERFECT and curious and eager.  The only problem I'm having is that my 2 tangs are such voracious eaters that even thought the Emperor is going after food, he's not getting as much as he should. <three words for the yellow tangs... barbless trout hooks, er...never mind> The result is my overfeeding which is obviously no good. <agreed...unacceptable> Any ideas? <remove the tangs to quarantine until the angel establishes dominance and familiarity with tank and other mates, then re-introduce the tangs into the Angels territory... but no guarantee. Tangs can be assertive> Will he just learn to get more aggressive when it comes to feeding time?  <hard to say... will suffer in the meantime> He's the biggest guy in the tank so he's not being chased or anything. <its all about attitude... just look at domino damsels; you'd swear they eat wolf cookies and drink gorilla milk every day for breakfast> Thanks Bob....keep up the great work. Rick <doing the best I can, Anthony>

Food Worthy of an Emperor Hey fellas, You keep giving such good answers so I'll keep asking. The Emperor I asked about the other day is now eating like a monster. He's taking everything I put in the tank and if the tangs grab something he basically pulls it out of their mouth. I have a rotation of brown, green, red algae going in the clip and I also throw in one cube of either frozen mysids, formula two, and angel formula each day. My question is, now that the emperor eats anything I give him, what should be his ideal diet? As of now he gets an equal amount of the "formulas" and the shrimp. Should be getting more or less of anyone of these? I hope I was clear. <For foods sound good to me. No changes recommended. -Steven Pro> Thanks for your time. Rick.. NY

Imperator Angel (Lymphocystis, John Milton's lament) I recently picked up a small Imperator Angel approximately 4" in length. I purchased him with having Lymphocystis at the time, the shop owner was going to flush him, and he was doing well up till 2 days ago. I was feeding him Brine Shrimp soaked in Zoe and occasionally Formula Two. He has quit eating. He is in a 10 Gallon Med tank, with a simple over the back. I can add a sponge filter that has been floating in my sump for a while for just such an occasion. I read at FFExpress that perhaps a water change and live rock would help so I have done that. I am also shopping around to find someone who sells Ocean Nutrition Angel Food, I read it is mostly a sponge base food source. I knowingly picked up the animal ill, but I saved him from a flushing, what can I do to keep him alive? <Place this animal in your main display tank... there is very little chance it will "pass" the lymph on to other fishes... and very good chance it will perish soon otherwise> I have already spent quite a few hours simply staring at him in the tank and trying to talk him into eating, but I have has no such luck. I have a sincere problem about caring to much for Marine Fish.  <Is there such a thing? I refer you to the writings of John Donne... "If a clod be washed from England's shore..."> I am always picking up sick fish and curing them. I am getting better all the time and I know that I am doing some good by saving just a few animals doomed otherwise.  <Perhaps they are in turn saving you> This is my first angel and I must say they are somewhat more difficult than I had expected. I thought a case of Lymphocystis would be a piece of cake to heal from all the information I had read, and I am still sure I can cure him if he would help by eating. All the water parameters are fine. 0's on Nitrate, Nitrite, and Ammonium. Ph is 8.3 and water is 79-80 degrees. Lighting is timed with 2 24" fluorescents. Help me Mr. Fenner. I have a great deal of respect for you and hope to meet you one day to express all you have done for me and my hobby. Your book is my favorite and quite beaten and dog-eared on the pages that the binding still holds. <Do place this animal in larger, more settled quarters... soak foods with a liquid vitamin preparation and iodide... the viral infection it has is an environmental "disorder", imbalance... strengthen it psycho-emotionally by improving its environment, nutrition, and in turn it will cure itself internally. Bob Fenner> Sincerely, Joseph M Howell

Problem with an Imperator. Help Hello, <Hi there> My Imperator has been progressively getting worse. (I attached pictures) <I see> For the first three weeks he was doing great. Then he started to show a few white blotches. They came and went every day. He continues to eat very well. Lettuce only. I am feeding vitamin-enriched lettuce. <Stop using the lettuce... terrestrial greens period... not much nutrition, too much likelihood of having/supplying nutrients to your system> Over the next three weeks the blotches became worse. Copper and two types of bacterial antibiotics (At two different times) are not doing the trick. <Likely not parasitic or infectious but water quality/environmentally derived> I have a protein skimmer going with carbon and a 25W UV filter. The blotches are too big for parasites and they are not fuzzy. It is almost like he is loosing color in those areas. Definitely a skin problem. Any recommendations? <Look to the myriad of ways you can improve water quality. Do you have live rock? I would add it, or add more... Place live macro-algae in the system... Check over the filtration components, and compare notes with the many FAQs on marine filtration placed on WetWebMedia.com... do you measure various aspects of water quality? Switch to human-intended prepared algae (e.g. Kombu, Nori...) and soak these in your vitamin mix instead... Read through the environmental and nutritional marine disease sections on WWM. Bob Fenner John

Cloudy Eye on Emperor Angel Hi Bob, I had emailed you a couple of weeks ago about getting a lunare wrasse and a maculosus angel. I have my lunare wrasse now and he's doing quite well. However, I couldn't find a maculosus angel that was large enough (4 to 5") to hold it's own with the 5" lunare wrasse. So, I purchased a 6" sub-adult emperor angel from an LFS. He has a bit of Lymphocystis on his fins but it's not too bad. He appears to be doing wonderfully in my tank - quite active and a great eater! However, his left eye has become fairly cloudy over the last week - it's not Popeye, just cloudy. I read on the internet somewhere that this is most likely a bacterial infection and I should treat him with antibiotics. <Mmm, no, not in my opinion... If "one-sided" (unilateral), this cloudiness is likely due to mechanical injury (likely a swipe with a net)... and though there may be opportunistic bacterial involvement I would NOT use antibiotics here. Perhaps a vitamin addition to the fish's foods...> I am concerned about stressing him by putting him in a quarantine tank so I've so far left him alone in the main tank and watched him closely. His right eye so far looks O.K. - maybe the slightest bit cloudy or I could just be seeing things :-) What should I do with this beautiful fish? Here's a picture of him, but you can't really see the cloudiness on his eye in the picture. <I would leave it as is... do you have a cleaner organism? Maybe a Lysmata Shrimp would help remove/expedite the loss of lymph, the cloudy eye clearing... very likely this problem will resolve on its own. Our coverage of this species and Lymphocystis, environmental diseases can be found on: WetWebMedia.com Bob Fenner> Holly L. LaClair-Bogedain
Re: Cloudy Eye on Emperor Angel
Thanks Bob! Wow, you got back to me very quickly! Is there a cleaner organism I can buy that won't get eater by a lunare wrasse and a flame hawk? I think those 2 fish would eat any that I could get... <I would try a Gobiosoma Goby... a larger individual if you can find it: http://www.wetwebmedia.com/neongobies.htm  Often recognized as more of a "helper" than a snack. Bob Fenner>

Re: copper Thanks, I'm in the process of curing 45 lbs of live rock, but it won't be ready for at least a week. <I would place a few pieces... Now. A good deal of the live parts are edible to the Angel (sponges, sea squirts), and the chemicals produced/released will stimulate its appetite.  Bob Fenner>

Emperor alone Hi Bob, I would just like to ask you one quick question, if that is ok ? <Sure> Basically, I run a 84"x18"x20" FO system. One of the occupants is an emperor angel. He is about 6", and almost full adult colors. I am about to embark on a long trip to south east Asia, and will not be back for at least 6 months. As a result, I am forced to strip down my FO system, as my Mother would not be able to handle it for me. However, I have suggested to her that if I were to sell on all other occupants, and just keep the emperor angel, that the system as a whole would be lower maintenance, and easier to manage. She has agreed to this. <Hmm> However, I am left to wonder, would the angel be "bored" in a system, by himself ??? The only tankmate I would let in the system would be a four line wrasse. Decor is simple Tufa rock. <I see> Would the angel be happy (happier???) if left to his own devices in such a system ??? By the time I return, and get the system back up to full potential again, it would be at least 9 months to a year. <I appreciate your concern... Is the system in an area where there is much, any "outside stimulation... e.g. your mother going by, change of lighting from the sun... If so, I suspect the Emperor Angel would be fine... and considering what its fate might be elsewhere, would be/am inclined to leave it where it is. One last comment. As it is obvious the fish and aquarium are important to you, I sense that they might form a bridge, link between your mother and you, your absence... a living link. Bob Fenner> Thanks Matt
Re: emperor alone
Cheers Bob, thanks for the reply. Was considering when I return the other fish, that I might get a couple of "bread and butter" fish, like a couple of blue damsels. These would serve a few purposes ......... (1) Provide additional stimulation for the emperor ..... something for him to chase and compete with etc, and interact with. <Yes> ....... (2) Feeding the emperor, there are bound to be small morsels of food that he wouldn't bother with, yet something like a damsel would relish ..... <Okay> (3) again on a note of feeding, there are bound to be small crevices that the emperor would not be able to get too, so any food in such crevices might be a problem. <Possibly> Hence, with this sort of thing in mind, do you feel it would be a good idea to put in a few small damsels ...... would a couple be sufficient ??? <Likely so, a good idea> I had considered a few hermits or the like ..... but I want to keep the system strictly FO, so that if any unforeseen problems should arise, all my mother need do is treat the tank with a copper based medication ....... <All good reasons. Bob Fenner> Thanks again. Cheers Matt

Emperor angel Mr. Fenner, I have a quick question about my juv changing emperor angel. He is a beautiful, healthy, thick guy that eats like a pig and has been in my 125g tank for about 5 months and has done great, way better than I expected. My question deals with a kind of weird thing that happens to him every once and awhile this is the second time it has happened since I got him). He stops breathing out of his left gill and his right gill starts breathing harder. The first time it happened, I was very scared, but before I had time to email anyone or go to my LFS and ask what was going on, it was gone. He stopped using it in the evening, and by the next day, it was working again. Now tonight, I noticed it stopped working again, so what is the deal. I have a Naso tang, a few damsels and Chromis, and a red general starfish in there with him and they all are doing well as well as the angel. The water parameters have been steady for at least 6 months. Do you know why his gill stops working? <Hmm, no... but have seen this a few times in/with other specimens... and like you state... doesn't seem to be related to any "cause" and stops just as suddenly as it started...> Also, I notice every once and awhile a few times a week), he goes up to one of the powerheads (and only a certain one, not the other one or a rock or anything else) and brushes his left side up against it and then just swims off. I know fish can get things in their gills that itch and they are just scratching themselves, right? <Yes... some scratching is "normal"...> Just like a human or dog with an itch. But why would his gill stop? It is kind of scary seeing his gill breathing so fast, and it makes me think something might be wrong with him. But then I know that he is very healthy other than this gill thing, and shows no signs of discomfort. Thanks for the reply in advance, and as always I love getting answers or ideas from somebody that has so much experience. Ryan Fick <Perhaps too much to eat... maybe something going on inside the fish... Bob Fenner>

Pomacanthus imperator and Pomacanthus maculosus Hello bob, my dealer had some show size angel and I fell in love with the 16 to 18 inches imperator and maculosus angel immediately I saw them. do you think at this size (16-18inches) are they easy to keep? <Decidedly not as easy to keep as ones collected at "reasonable" (a few inches) in length and raised in captivity... Fishes (actually all animals) collected "large" are less adaptable to captive conditions... like food acceptance, getting along with other "novel" species... And shame on the collectors and retailers for extracting adults... leave these in the seas to reproduce.> at the moment they look great. if you were me which one will you purchase? the maculosus or the imperator angel. and why? <Mmm, neither... as I am morally opposed to their collection in the first place. Bob Fenner>

Pomacanthus Imperator Hi Bob. I really enjoy and appreciate your site. I was wondering why there was nothing like this on the net and then I found your site last week. Excellent!  <Great! Glad we found each other> Here's my question: I have a juv. emperor angel. I've had him for about a year now and he seems to be making good progress towards his adult coloration. Is it normal for a captive specimen to develop a normal adult color pattern?  <Yes, over time... sometimes with not much growth> I seem to remember reading once that captive juveniles rarely attain full adult markings. Is there anything specific I can do to encourage or assist the change (specific foods, supplements, etc.)? <Hmm, nothing specifically... Keep up regular maintenance, use live rock (replacing some every year or so), providing a mixed diet... possibly enriching same with a vitamin and iodide adjunct... Bob Fenner> Thanks. Again, great site! Walt

Emperor Angel Hi Bob! Hello from HOT & HUMID Chicago! It's been a month or so since I last wrote about my Emperor (adult) that seemed to have fin rot. Since then the rot has stopped and it seems like the pectoral fins are slowly growing back. <Ah, good> In the last week he has seemed somewhat lethargic with his eating. He still reacts to me when I come up to the tank and comes up and eat out of my hand, but his intake is at least half of what he was eating. On the other hand he seems to hide more than usual (normally not much). I also noticed that some of his feces looked white and stringy (almost like plastic). I did my scheduled water change this week (10% every month) after I noticed his symptoms. not much change in the last two days. <Yikes... the lessened appetite and fecal appearance may well be indicative of internal parasite presence... You might want to administer an antiprotozoal to this fish's food> Besides that, nothing is out of the ordinary, he has lots of places to hide if need be and is the largest (king of the tank) fish in the tank. As always thanks for your help! Chris Goldenstein <Do study up on Vermifuges, Metronidazole/Flagyl, perhaps Piperazine... Bob Fenner>

Re: Emperor Angel (internal parasite problem?) Hi Bob, thanks for your reply. I couple of questions. I read up as much as I can find on the treatments listed below. In most cases it is preferred not to use any of these due to their toxicity. Is there anyway that something like this will pass? or will it just get worse? <Hmm, fin rot (almost always water quality related), yes, with time, optimized conditions... and often yes about the internal difficulties> One other thing, will trying to get him to eat fresh garlic work/help? <A lot of people endorse this approach. Don't think it harms the animals... I cook with this family of plants extensively... Bob Fenner> Thanks again! Chris

Imperator Angel Hey Bob, love your answers I have learned a ton from them. I have an imperator Angel who is a juvenile, still blue with white stripes. A while ago his face started losing color turning white. After a while as it progressively got worse, I realized it wasn't a discoloration but his face was slowly being eaten away by something. Now it been months, and his face is still all white while the rest of his body is fine. He seems extremely healthy, eating, even sometimes pestering other fish. I don't know why this happened or what caused it but I wish for him to get his facial skin and coloration back. Like I said it's been months and it hasn't gotten any better just stayed the same. Is there anything I can do?? <Yes, much... what you describe is a type/degree of what is termed HLLE, Head and Lateral Line Erosion... this condition has several possible "causes"; stray electrical potential, aspects of "poor water quality", and nutritional deficiencies... the latter are the most common... with folks advocating various treatments, including the use of "miracle mud" or just good live rock and macro-algae culture, and the addition of vitamins and iodide (iodine) to the animal's foods. Do avail yourself of at least the last protocol. More on this scourge under HLLE on our site: www.WetWebMedia.com. Bob Fenner> With thanks in Advance, Tom D

Emperor Angel Advice Hi Bob: Hope things are going well. I needed some fish advice and I  thought I'd ask an expert, if you don't mind. I e-mailed you regarding your book back in 98 (time flies!). <Indeed. Tempus fugit> I recently bought an adult Imperator Angel. I have had him for about 3 weeks and he is eating like a horse. The only problem is that on  his right side, his eye is somewhat cloudy and one of his pectoral fins was not clear but more opaque. The fin suddenly got a bit ragged and he seems to be twitching a lot and will sometimes make a quick dash across the tank. His colors seem good and he even eats from my hand. Does this sound like a parasite? <No... very likely just the result of a mechanical injury... a "bump in the night" or the after-effects of a net-rub.> Should I do a freshwater dip or just hope he keeps eating well and it might run it's course.  <The latter> I hate to pull him out, it usually causes a lot of stress on any fish. what do you think? Once again, thanks for your time. Chris Goldenstein <Please read over our site: www.WetWebMedia.com re this species, the genus Pomacanthus and the Family Pomacanthidae FAQs sections... many cases like this. Bob Fenner>
Re: Advice
Bob: Great website! I have been looking for something decent, the Emperor FAQ was quite useful. These fish (emperors) act very funny with their antics. <Yes, very intelligent fish> One more for you. I have a 95 Reef Ready tank with the following: Adult Emperor 5" Asfur Angel 2.5" Lemonpeel 2" Flame 2" Adult African Clown (formosa) wrasse 4" Sixline wrasse 1.5" mixture of corals (dead) and 6-7 pieces of live rock (lots of hiding places). 25 watt UV and Skimmer. I know that this tank is stocked up to the max at this point, any comments? <Umm, total agreement with your stocking assessment... as of now, and a caution that you are going to need a much larger system soon (let's say three hundred gallons plus) or to trade in the Asfur in a year or so, and then the Emperor... Bob Fenner> Thanks again for your advice. Chris

Fin rot and sores on Imperator Bad news. Apparently, I burned my fishes with too much copper. My imperator angel now has his tail and pectoral fins damaged (missing portions) as well as suffering from body sores.  <Oh no...> I've been feeding him Zoe-soaked Mysis shrimp and Nori, and he eats well, as do all the fish in the tank. The sores seem to be getting a little smaller, kind of brownish-scabbed over, but still, this beauty does not feel well and my heart aches for the damage wrought on him by my mistake. Should I wait it out to see if he self-heals or treat him/the tank with an antibiotic? <Just wait...> He also is covered by little white things, not cyst-like as in ich, but kind of like tiny tufts, about 0.5 to 1 mm each in size. My Koran angel, while not suffering from body sores, seems to have a little of the edges of his fins eroded as well, and the yellow tang, while not having any fin erosion, seems to have some of the same white tufts (for lack of a better description) on his tail fin. <Could be some manifestation of the burn... or indirectly Lymphocystis... described on the www.WetWebMedia.com site under "Environmental Diseases"... a similar description physically> A couple of the other fish do, too (on their fins), but not to the extent of my imperator. What to do, what to do?  <Maintain high water quality, use cleaner organisms (shrimp, gobies)... and be patient> The hospital tank has turned into a disease tank. If you recommend treatment with antibiotics, please be specific about which one, and advise whether the neon gobies I have coming in a couple of days should go into the tank, and whether I should put my cleaner shrimp (3) in the tank now.  <Do both, now and when you get the gobies...> Bear in mind that I did treat the bare tank with copper and removed it with water changes, poly-filter pads, and carbon. I've also put some peppermint shrimp in there just to make sure they wouldn't croak...they've been in there for 3 days. Thank you, Sherri <Steady on my friend. Bob Fenner, in Cabo San Lucas>

Re: 90 gallon FOWLR Thanks for your response!! Do you think I could get a year and a half to 2 years with the imperator if I started with one that's around 2" in length to start? thanks again <Better to start with a larger specimen (see the www.WetWebMedia.com site re this species), and plan on a larger tank sooner... Bob Fenner>

Emperor/help Mr. Fenner, I just bought a juv emperor from ff 10 days ago. He is just about to change from juv to adult and is 4" big and thick. He has been in a qt tank for over 10 days and today I went ahead and added him to the main tank a 125g w/LR over 100lbs, water is 0 ammonia, 0 nitrite, little to no nitrate, temp 78*, sg 1.024, ph 8.2). I used the main tank water to start the qt tank and then did water changes 3 times a week.  <All sounds good so far> He was very scared and stressed in the beginning, but after about an hour he was fine and swimming around. Ever since then, he has done fine. I have feed him every other day and he eats. So I am so happy so far, except what I am seeing now when I got home from a run. I acclimated him for about 1.5 hrs this morning and then put him in the tank with the lights off for about 2-3 hrs. He seemed fine after about 15-20 min.s. I even gave him some angel formula and he ate it. He was swimming around and interacting with the Naso and damsels. But now about 5 hrs later, I come home and find him breathing pretty heavily and faster than he should be breathing. I checked all parameters before I even put him in this morning and everything is great. And on top of the faster than normal breathing, he also just swims on the side of the tank nearest me and my CPU and just keeps circling back and fourth looking at me. I am very concerned but don't know if I should be or not. <Hmm, likely nothing... other than the cumulative stress of being more... and so much newness the last month...> It may just be he is spooked or stressed and just breathing harder but why wasn't he like that in the morning and afternoon)? Is there a tiny amount of ammonia that is not showing up on the water testers?  <Doubtful> I need help ASAP because it is really scaring me how heavily he is breathing. It's not like as fast as if the fish was dying, but pretty fast. Any help or answers as to what to do, would be appreciated. I am also going to do about a 20g water change of the total 125g tonight or tomorrow morning. Thanks, Ryan <Not much more to say here... other than that what you describe "does happen"... and generally solves itself in a matter of a few days on its own... please try to be patient here. Bob Fenner>

Emperor Angel Bob, I have a 120 gallon diamond shaped tank in which I house a number of species of Marine fish. My Emperor Angels behavior has puzzled me for some time now. He/she seems to stress very easily. He/she swims to the back of the tank and rests on its side, breathing quite frantically, whenever someone gets too close to the front of the tank. He/she sometimes can be seen only breathing out of one gill. He/she also turns blotchy. I have had this fish for about 9 months now and as I said before, I am quite puzzled, because it happens quite frequently. Is this normal behavior for this species or might their be another angle to this angel? Thank you for your time, Doug <Hmm, yes, normal for either a "chintzy" specimen or one that is "being stressed"... this is a small volume for this species... and it needs "psychological" distance (rock, other decor) to "get away" from you, others... Bob Fenner>

Emperor Angel Bob, I recently ordered an Emperor Angel from FFExpress. He is about 3 1/2-4" and looked great when I got him. I placed him in a quarantine tank for 10 days and everything looked good except he didn't seem to be too excited about eating. <Typical... a very trying journey> I hoped that this would get better once I placed him in my main tank. After placing him in the main tank he has pretty much just hung around the bottom of the tank among the live rock. He still doesn't seem to excited at all about eating. I have tried frozen brine, plankton, flakes, seaweed selects, Spirulina, and angel formula. I have seen him eat some frozen brine and angel formula but ignores just about everything else. When he does eat, he doesn't come out to eat. He very lazily eats what just happens to fall right in front of him and even then he is very slow and lazy about it. I'm not sure if there is anything wrong with him because his colors look great, he breathes normally, and doesn't show any outward signs of anything being wrong. Another thing that concerns me about him is that he only sticks to the rocks.  <This is what juveniles of the species do in the wild... where they get their food (sponges, tunicates, algae...), and protection from predators...> He doesn't come up front in the open ever and never goes up top to eat. I have noticed him hanging out with my Foxface, which also isn't a big swimmer, and it almost seems like he is trying to hide his face. As I look at him I see him try to find a niche in between rocks and put his face in there. Sometimes, he even almost lays down in the sand behind a rock which seems like he is either trying to go under it or just hide. Does this sound like normal behavior? <Not unusual> Nobody picks on him or anything. The only other fish in the tank are a green dragon wrasse, Foxface, and two orange diamond gobies in a 125 gallon tank with around 70 pounds of live rock, two emperor filters, and a sea clone skimmer. All my water parameters are fine except that my nitrate is at 10 ppm and nitrite is at 5 ppm.  <What? is that a typo? Five ppm of NO2? This is way too much... I would upgrade the skimmer and cut back all feeding till this is under 1.0ppm... and likely increase the time your lights are on to help...> I think my nitrate level is a little high only because I keep trying different foods trying to find something that he likes. I would appreciate any suggestions you may have on what I can try feeding him and any thoughts on his apparent shyness and strange behavior of trying to hide. Thanks, Gianluca <Patience my friend. Get a better skimmer, try some live food, don't worry unless the specimen is getting thin. Bob Fenner>

listing emperor angel Hi Bob, thanks for your reply. Sorry to pester you so often with so many queries .......... this will be the last mail for ages .... I promise. <No worries> If I need to move my clown trigger in order to be able to get cleaner shrimp, then I will, but I would rather avoid that if at all possible......he was a gift, as well as the fact I really like him .... but if he has to go, then so be it. You mentioned other facultative cleaners, other than shrimps, namely you suggested I looked at the small Bodianus wrasse, and Heniochus butterfly. I have also considered the 4 line red sea cleaner wrasse. Are there any other possible species to consider ?  <Many... do I list them on my symbiosis piece on the WWM site? Otherwise, am sure the Net searching would turn up exhaustive naming.> In your opinion, not including shrimps, what are the best facultative cleaners ??? <For a large Triggerfish? Maybe the Hogs/Bodianus or juvenile Angelfishes...> I assume that neon gobies would be eaten by the trigger, and maybe even my angels !!! Will Heniochus remain facultative cleaners into adulthood, or only as young fish, and would they be able to get into the gills of my emperor ??? <The gobies might well persist... as they're often identified as cleaners rather than food...> He is only 5" ? How about the Bodianus wrasses ....... could you suggest a few suitable species, preferably ones that continue cleaning into adulthood. <None into adulthood... axillaris, anthioides... others if more available, less pricey...> My emperor is seems to be displaying the gill flaring more and more, so I am anxious to get something sorted out ..... I am going to move the trigger short term, and put the shrimps in the tank ....... but that will only work for a limited time .... I am really looking for a more long term solution. I would appreciate your opinion on the best facultative cleaner for the job. Lastly, on a different note, while looking at the web page on Bodianus wrasse at wet web media, I see that the Cuban hogfish is a facultative cleaner while young. But I presume he would get too big to be an effective cleaner as an adult ? <Just don't clean when older/larger...> In any case, I would be interested in this species regardless of cleaning. You mention they are seasonally available .... when is the "season" ??? <About now for the next few months... affected by weather, collecting conditions, need for money by diver/collectors...> Thanks again for all your help. I really appreciate it, and I will not be bothering you again for a while (unless an emergency occurs !!!). Regards Matt (Co. Cork, Ireland) <Again, never a bother. Bob Fenner>

Ailing emperor Hi Robert, Maybe you can help. I've had a changing juvenile emperor anger in my tank for 3 weeks now. It has white "clumps" on the ends of it's fins and on both of it's gill spines. Besides the unsightly spots, it eats normally, swims normally, and interacts normally with the other species in the tank (150 Gallon fish only). None of the other fish show signs of the same ailment. What am I up against? Thanks, Scott <Almost without doubt this is a case of the environmental/viral condition called Lymphocystis. Take a read over the materials on the subject stored on the www.wetwebmedia.com site. Lymph can be cured... Bob Fenner>

Listing Emperor angel Hi Bob, Hope things are well. Getting out of AOL then. Didn't realize, I mail directly to the hotmail in future;-) <Ah good, and yes, tiring of their thumb-numbing delete-exercise you-paid-for it advertising... and auto-formatting problems of moving Q/A mat's to the site.> I am writing in hope that you can advise me about my emperor angel. Up until recently he has been doing really well. However, lately he is behaving very strangely. In general he appears in good health, eats well, good colour etc, still the most dominant fish the tank. What worries me is this. He keeps going through periods of inactivity. He hovers close to the bottom, and then begins to list to one side. He keeps leaning over until finally he is almost horizontal ........ (about 10 degrees angle) And then he hovers there, in that position for ages, until something stimulates him to move, then he swims off quite normally. (i.e. to chase another fish, food, etc) Another thing I notice is that sometimes he is "flaring" his gills out for no apparent reason, usually while he is going through the "listing" thing. He opens them right out like as if he is posing for a cleaner shrimp. <All sounds "par for the course" with this species but the last... Do you have a cleaner of some sort in the system? I would add a species of Lysmata Shrimp myself... if it will go with your other livestock> When this behaviour began, he used to move close to the rocks, and tilt his body such that it was parallel to the face of the rock. At first I thought he was probably looking for the cleaner shrimps so he could get cleaned, because this was where the shrimps used to hang around. However, there are no shrimps in the tank anymore, I took them out ages ago, because I got a triggerfish. <Oh... well, I would look into some other facultative cleaner types then... maybe a small Bodianus wrasse species? Heniochus butterfly...> Now he typically illustrates this "listing" (tilting) and gill flaring exercise at the front corner on the tank, just over a small piece of LR, that is only a couple of inches or so ....... i.e. there is no way he could think there was a cleaner shrimp hiding near by. <I wouldn't go that far... this "behavior" is likely more than learned... the fish is "seeking" help... very likely> Can you help me ??? Have you heard of this type of behaviour before ??? Is it a serious thing, and can it be treated ??? Does it need to be treated ??? Do I need to do something ??? <Get another type of cleaner, move out the trigger, risk other shrimp...> As I said, he is others in good health, and all the other fish in the tank are doing fine, including the queen angel (which I assume has more or less the same needs as the emperor, thus I count out any environmental conditions). He is not off his food, or showing any signs of sickness, and is breathing normally also. The only thing is that one of his eyes was cloudy for a short time, but I think this was only because the tank needed a water change ........ I had missed out on the regular biweekly change due to sickness ....... but the emperors eye cleared up fine after the water change. <Cloudy eyes? Not a good sign... do watch your water quality, and numerous whips with a wet net for missing the water change, regular maintenance...> Thanks for reading, and for any help you can offer. I would really hate to loose this guy now, I have had him for ages, and he has grown so much, and otherwise seems to be doing so well. Regards Matt (Co. Cork, Ireland) <Maybe add a couple of teaspoons of baking soda (sodium bicarbonate) per water change to increase/boost alkalinity... Otherwise... Bob Fenner>

Question on Imperator Angel Mr. Fenner: First off, thanks for all the help and advice that you offer to marine aquarium folks like myself. I know it has helped countless people. <You're welcome. Deeply gratifying to hear, be part of> Now to my question, and the problem I am having. I have a 150 gallon tank, set up with live rock, a few leather corals, and some fish. The tank is maintained in a very meticulous way, with systematic partial water changes, monitoring of Ph, KH, Nitrates, Phosphate, and Calcium. The water is always crystal clear, and there is some nice coralline algae growth. The following are the readings on the water: Temperature - ranges from 79 to 81 degrees F Specific Gravity - kept between 1.021 and 1.022 Ph - 8.3 KH (in dKH) - 10.6 Calcium - 380 Nitrates - less than 10 ppm Phosphate - 0 Ammonia and Nitrite - 0 Fish In The Tank: Imperator Angel, Naso Tang, Purple Tang, Harlequin Tusk, Niger Trigger, Fox Face, 2 Blue Damsels, 2 Cleaner Gobies I have had a recurring problem with the Imperator showing signs of Cryptocaryon, primarily associated with its pectoral fins. I have had the fish for two months, and it was at the aquarium store for a couple of months before I bought it. The angel is in the final stage of changing from juvenile to adult colors. <This species is "touchy" in the way of easily contracting the common reef fish scourges, unfortunately> The other fish in the tank have not shown any signs of parasite infestation, and some have been in the tank for a few years. The Imperator's body does not show any signs of parasites, but there are splotchy areas in the pectoral fins, and the fish frequently rubs up against the side of the tank or smooth rocks. The rubbing seems to be directed toward the pectoral fin area. During the two months I have had the angel, I have given it fresh water baths, and also put it in a quarantine tank with copper safe for two and a half weeks. When I took it out of the quarantine tank and put it back in the main tank, it showed absolutely no signs of parasites, and was no longer rubbing up against the walls of the tank. After being back in the main tank for about a week, the splotches and the rubbing returned. I now have the angel back in the quarantine tank. Throughout all of this, the fish has remained a very outgoing and friendly fish. Even after being caught and put in the quarantine tank, the fish was eating out of my hand a few minutes later. The fish has remained active through all this, and does not act like a sick fish. The splotchy areas and the rubbing, however, make it clear to me that there is a problem. Because of the live rock and the leather corals, I know I cannot use copper on the main tank. I do have an ultraviolet sterilizer on the tank (with a new bulb) and an ozonizer hooked up to the protein skimmer. I may be wrong, but it appears to me that parasites are always around, to some extent, even in a well maintained tank (unless a copper treatment is in use). <Yes to the omnipresent possibility of "disease" (do read through "The Three Sets of Factors" that determine health, posted on the www.wetwebmedia.com site... you'll find yourself agreeing/nodding so much that you'll resemble an old Beatles doll in a fifties Chevy with poor shocks. A UV would likely help, I would not use copper... anything improving water quality and nutrition would be beneficial as well... Like more, better live rock, macro-algae, a sump/refugium...> Am I correct that parasites are always present to some extent, but that they only tend to become a problem if the water quality goes down or a fish's immune system and natural defenses go down? Is the Imperator Angel a fish that is prone to parasite attack, while the other fish in my tank do not show any sign of it? Is there anything that I haven't tried, that you would recommend to help solve this problem? <Not linear, mutually-exclusive events... some parasitic and infectious load is present in all systems, some organisms with complex (intermediates) life cycles are more easily excluded... there is an interplay twixt "initial state (genetic and developmental), suitability of the environment (a huge category) and the presence/degree of infectiousness of disease-causing organisms... read the above citation> I could return the fish to the aquarium shop, and trade it for another type of fish. I hate to do that, because it is a beautiful and outgoing fish and it has become a member of the family. But I don't want to continue subjecting it to fresh water baths and quarantine. <Won't help the specimen to be moved, or you/your sense of place in both your lives> Thanks a lot for your help. Pete Vosbury <Be chatting my friend, Bob Fenner>

Development of my imperator Hi Bob, I wonder if you could please give me your views on my imperator angel, namely on his stage of development. I hope you can open the file above, most folks can open .tiff files, using the imaging software, if not using ms paint. If not I can forward a bit-map image. <Shows okay... a bit fuzzy for 30k> He is about 4.5" or so, not including tail fin. I have him now for about 18 months or so, in which time he has developed from a juv. of about 3" or so, to his present stage. Would this seem like an ok rate of development, or does it appear slow to you ? <Looks fine, and healthy... good semi-adult coloration... okay size... better to not push this species on either aspect of development... live happier, healthier lives going slow> If you feel he may be underdeveloped, then I would like to take steps to increase his development (general health and happiness) rate. I am told by some folk that the about 1" a year is the norm, and up to 2 years for a full colour change ............ on the other hand I know of a guy who grew a 2.5" specimen to 8", with full colour change in about a year !!! <Not a good idea in my estimation...> I know things vary etc, resulting in different rates, but I was wondering if my guy is on track, or if he is lagging behind.  The picture portraits him in slightly different colours. His yellow tail is not quite as bright a yellow as that, and his stripes have a yellow tinge to them, rather than the white that the pic shows. Thanks for taking the time to read. Regards Matt PS. I am looking into the diving cert, and hope to get on a course a.s.a.p. :-) Cheers. >> <Ah good, and no worries re your Imperator... it's doing fine and will continue to do so under your care. Bob Fenner>

Quick Question Hi Bob. About a month or so ago I wrote you about my 110 gal all fish setup, which has now been setup for 3 months. At that time I had a 4" juvenile colored Imperator Angel and a 2.5" cleaner wrasse. I'm happy to report the Angel is doing GREAT, totally disease free, very active, brightly colored, and accepts 7 different kinds of foods!  <Ah, good news> The cleaner wrasse is great, too. Just last week I added a 3" gold-rimmed Maroon clown, and (against your advice, but I couldn't resist trying) a 2.25" juvenile Atlantic Rock Beauty (Holocanthus Tricolor). At first Mr. Imperator bullied him, but the Rock Beauty is such a pesky little thing that he wasn't daunted, and he feeds great and is VERY ACTIVE, and now the Imperator has JUST ABOUT accepted him fully in his "kingdom."  <Wowzah, very surprising and good news> I'll probably add a few butterflyfish and either a Red Sea Purple or Sohal tang, and that's it. <Probably about all the 110 can handle for now>  The Emperor still dominates my tank, and above all, I want him to continue to grow and prosper. My question is, what is the max size you think a 4" Emperor can or will grow to in a 110 gallon tank? <About eight inches... which can be pushed into about a year, but will be much better to drag into two, three... until you can offer it larger, better quarters> Dimensions are 30" H x 18" W x 48" L. I'd like to keep him in this tank until he's 8 or 9 inches, and then move him to a bigger 150 or 180 gallon, which I'll probably buy next year sometime. Also, how long do you think it'll be until this fish reaches the aforementioned 8 or 9 inches? <As stated... a year or more depending on feeding, other factors... will be much happier, healthier in a larger system> As always, thanks for your advice. One of these days soon I'm going to pick up your book on Marine fishes, I hear it's pretty great. <Me too> Regards, Scotty Knight, Erie, PA >> <Bob Fenner>

Juvenile Empower Angel Bob, As you responded so well to my last e-mail of sometime ago, I am writing to you on another subject - namely that of the swimming condition of my J.E. Angel. He is about 5" long and still very much in his juvenile state and lives in a 60UK G fish only tank with live sand and external wet & dry filtration. Skimmer is a SeaClone as I have not changed it yet but will hopefully soon. His body is OK with no markings or sores etc, however he is swimming very "awkwardly". When he swims upwards he uses "all" his body to propel himself - that is what it looks like and he also seems to be spending a lot of time by the skimmer pump inlet. He is not caught by the pump as he can swim away quite well - maybe he likes it there? <Maybe... does it ever swim "normally"?> He is feeding OK with frozen brine shrimp (1/2 a cube a day) + flakes + a square of algae sheet. I have had him some 5 - 6 months and he has only been like this for the past month or so, before that he was fine. The water parameters are fine - checked last night - pH - 8.6 (always has been), Ammonia - 0 , Nitrite - 0 , Nitrate - 20 & Phosphate - 0.25. Any thoughts would be welcome. Best regards, Scott PS - LFS has stated that my wet & dry filter (Eheim 2329-85) would overcome the usefulness if the skimmer and therefore it would not be necessary to change the skimmer as it would not pull anything out! Any response?? >> <Don't understand the logic behind/in front of the above stmt... and disagree with same... the SeaClone is a gimmick... and you will definitely see more and worse/better "gunk" removed via a real skimmer... with or w/o a/the wet-dry... Re the angel, something may be amiss (evidenced by its swimming), but... as to cause/cure? A genetic, developmental anomaly? Lack of nutritional component? Some aspect of metabolite poisoning? Many other possibilities... I would use activated carbon once a month, get/use a better skimmer, and vary the diet... Bob Fenner

Emperor and crypt We have had our Imperator Angle for approx 2 years in a 150 gal aquarium. About 1 week ago we started noticing white spots on her body. The spots resemble when a fish becomes stressed or angry and their color changes temporarily, then returns to normal. The Imperator has never acted stressed and has basically always ruled the tank. The white spots are not raised. None of the other fish seem to be sick. She is eating normally but the spots seem to be getting worse. She has them all over her head and body. Do you know what these spots could be and what we can do about it? >> Are they very small, almost salt grain size? If bright white, this is likely the marine parasite call "ich" or Cryptocaryoniasis... if rusty colored, it may be the algae parasite called velvet, or Oodiniumiasis... If the markings are symmetrical and mainly around the head, this might be indicative of a poor water quality condition... are no other fish species affected? This would be unusual if any but the water quality are the cause... I would do some reading and add something in the way of biological cleaners at this point to help tilt conditions in your large angel's favor... Bob Fenner

Imperator angel Bob, I have noticed that FFExpress often has their juv. imperator angels on sale. I would assume that the low prices create a large volume for the items that are on sale. This may mean that people are purchasing these fish that you say are difficult to keep healthy. <It's possible> I have read your Q&A and seen someone asking about HLLE on their imperator. My juv. imperator angel has also started to develop HLLE (I think?).  <Very common... environmental, nutritional difficulty with this species> The fish has enlarged holes around its face and patches where color has been lost. A couple of days past and I started noticing that the patches had progressed toward the tail.  <The same... maybe take a look at the species profile, nutritional disease, HLLE materials stored at the URL: www.wetwebmedia.com... I would spiff up water quality... add vitamins and iodine to its food... strongly encourage the implementation of an algae/mud filter... the last REALLY works on HLLE> The fish store assured me that I had created the disease by allowing electrical currents into my tank. The problem could be rendered for ~$20. I went home and read what your book had to say about the disease. Luckily, my judgment was correct as you also believe the electrical current theory to be anecdotal. I had just added a 30 gallon sump to my 75 gallon tank, so I feel that water quality was not a big player in the disease progression.  <I concur, and thank you> After checking my notes, I realized that I had only been feeding the fish the Formula I frozen food from Ocean Nutrition. Normally, I use Formula I and Angel Formula. I started giving the fish only Angel Formula and within 2 days the spots had disappeared. It may be a coincident, but I thought it was interesting since you book states that the cause may be water quality and/or diet. The angel has also been swimming around the tank much more since the diet change.  <Ah, a good intuitive statement and useful anecdotal account... You have just saved several (from the Middle English meaning "many") Pomacanthus imperator angels...> I thought that your comments on the subject may be valuable since the FFExpress frequently advertises the juvenile imperator angel. Jeff >> <And I thank you, again, Bob Fenner>

Emperor with Tumor Bob, I am the guy that wrote to you recently on the Emperor with the mouth tumor  (9" Red Sea, on Oxytetracycline food), subsequent to your recent Q&A covering  the very same subject. I dared accept the challenge. My son and I caught him, placed him in a five  gallon bucket with aquarium water, prepared "Dip Away" solution, and cleaned  several small utensils such as tweezers, knives, etc with alcohol. My son  held him as I plucked slowly the tumor in multiple pieces. We dipped him in  the Dip Away solution and placed him back in the main system. Well, he is doing great so far (about four or five days now). He is eating  like a pig. No signs of any infections. I did leave a small stump as I was  afraid to accidentally cut his mouth if over trimming. Do you think this  will be OK? <I'm hopeful...> Should I have taken it all off and chanced more damage?  <Hard to state... there are trade-offs, compromises...> My guess is he will be just fine given the results to date. What are you additional thoughts? <None worth positing here... congratulations> Thanks for the great advice. Regards, Carlos >> <You're welcome, Bob Fenner>

Problems with my Emperor Angel Hi Bob, I am writing about a problem with my newly bought Emperor Angel. I have a 125 gal. FO tank, only because I live in Hawaii and anything related to having a reef is illegal here?  <Do know of the laws in the fiftieth State, and disagree with them... > It has been set up and running for about 8 months now. All my chemistry is just about perfect. Anyway I bought my Emperor about three weeks ago, when I put him in a QT for about 10 days. Everything seemed fine, so I put him in the main tank. About two days later he started to scratch at both his eyes. It's now to the point where you can see little rub marks on the clear part of both eyes. I have had ich in the past, about three months ago. I treated it with copper sulfite and everything was good and still there is no signs of ich on any of the other fish or the Emperor, except for the scratching. I also don't have a cooler, so I use a fan for evaporation, therefore I am always replenishing with RO water. Any advise at this point would be great. Thanks for all the help you have already given in you column and book.  >> Sounds very much like a chemical or physical anomaly to me... not necessarily or directly anything "catching"... What I would do: Add a biological cleaner, my fave choice, one or two Lysmata amboinensis, the Pacific Cleaner Shrimp. And add a pad of Polyfilter to remove metals, possible biochemical problems... And lower your specific Gravity to about 1.018 to diminish the infectiousness of possible lingering parasites....increase gas solubility, lest there is insufficient aeration, circulation in this system. And place some macro-algae, even Ogo (wish I was eating some Ahi poke right now!) for "comfort food", improving water quality, absorbing some of that probable biochemical anomaly.... Bob Fenner who will be in touch
Re: Problems with my Emperor Angel Hi Bob, again.... Well today I took the Emperor out and put him in a QT. He was looking worse than yesterday. His fins are almost totally cloudy now and spreading to the gills. He is also breathing more rapidly than normal. Also, he was hiding horizontally under some rocks, which really scared me when I first got home. He did come out to eat, but went strait back to hiding. <Bizarre... the behavior and looks you describe are very bad... but the fish came out and ate? Unusual> So let me get this strait, you don't want me to put any kind of medication in the QT. I did use a slightly lower specific gravity (l.018) in the QT. I just wish I knew what is wrong, so I don't make the same mistake again. I followed your advise and bought a poly filter and put it in the main tank, but of course there is never an immediate cure. Thanks again for any advise. Mark >> <I would not have moved the animal... but if I had, I would have run it through a Nitrofuran compound (probably Nitrofurazone) dip (about 250mg per five gallons, in slightly lowered spg water, for ten minutes) before placing it in quarantine... Keep your eye on it, Bob Fenner>

Emperor Problem Bob, I have a 9" Red Sea Emperor Angel with the same identical problem you note on  today's Q and A. He has had it on the lower part of the inside of his mouth  since I bought him (over a year ago) and always stayed the same size. It has  shades of white, black and even red. It only seems to bother him in the  sense he is selective in eating smaller bits of food but continues to have a  great appetite. Two weeks ago, it suddenly erupted into many more "chunks".  I dipped him three consecutive days in Aquatronics Dip Away for 4-5 minutes  and one of those times, he expulsed a chunk of one into the water when placed  back in the main tank. It looked like a tumor with evidence of some blood  where it was attached. It has improved but not gone away completely. I have  been feeding him Oxytetracycline (so I have been told) food which he seems to  enjoy. Do you really think I should mess with trimming this "thing" out of  his mouth? It is something I actually considered but chickened out of.  After all, it is only about $300 to $400 to replace this prize fish. How  would you address the possibility of an infection after the removal? I have  a 225 tank which will be very expensive to treat with antibiotics and he is  much to big for a hospital tank. Will the "Oxytetracycline?" prevent the  possibility of an infection? It is really interesting to hear this is not as an uncommon problem as I  thought it might be. Thanks for all the help. I really enjoy the column. Regards, Carlos >> Thank you for writing so lucidly... Yes, there is a fine line between "just waiting", hoping that such tumors will solve themselves... and going so far as to effect a surgery... If the animal ceases feeding, your hand may be forced to the latter... Secondary infection is a real concern in exposing a fish through this sort of manipulation... and is best dealt with through oral administration (feeding), and/or injection of appropriate antibiotics... And of the broad-spectrum, gram-negatives, Oxytetracycline is often used in foods... If you have enough "emotionally invested" in this animal, I would check with a local veterinarian who has some background with fishes (call and ask around, other vets know who these folks are in your area), and have them assist you in the actual surgery and injection of an appropriate amount, type of antibiotic. They are welcome to contact me re the last for opinions. Bob Fenner
Re: Problems with my Emperor Angel
Thanks for the advise. Today, I also noticed that the two front fins and the black area of the body, where the fins attach, seem to have cloudy patches on them. He also seems to be hiding more than normal, although he ate normally today. I am getting worried now and think I should take him out and put him in a hospital tank?  <I wouldn't move this animal... look to improving, keeping the present environment... moving it at this point is very stressful> What do you recommend for treatment?  <Zip, nada, nothing> I am kind of new at this and hope I don't do anything wrong! About your reply, I am kind of confused about gas solubility, I have two Rio 1700's for circulation. Is enough?  <Circulation is not equivalent to gas solubility, exchange... air stones, air intakes on your powerheads should be employed if there is any doubt of saturation> Also how do I go about getting macro-algae?  <Order them and place them... in the main tank, a lighted sump, or both> I thought that was something that came when you get live rock, which I can't get here? <?> Is Ogo a form of macro-algae, or fish food?  <Both> And finally, I have a porcupine puffer, will he try and eat the cleaner shrimp if I were to put them in? <Assuredly> Thanks again for the speedy response. I don't get much help here from the LFS. >> <Then seek to help THEM... are you on the Big Island (call Mr. Stokely), on Oahu? Call Randy Fernley at Coral Fish Hawai'i... tell them I sent you...> Bob Fenner>

Question: I sure hope you can give me some advice on this one. I have a (nearly) adult Pomacanthus Imperator, approximately 12-14 cm long. I acquired it from FFExpress last fall. Within a month or so of introduction to my tank, it began to developed a few small, 'pimple' like pumps, slightly discolored. They have continued to appear and spread in patches on the fish, and are getting worse. Most of the earliest patches have now gone away, and left only faint scars. What's more, they don't seem to bother the fish, with the exception of one time when a particularly bad patch developed a secondary infection. I treated that with SW Maracyn, and it quickly recovered. It seems to be a strong fish, and is an outstanding eater, although I have a tough time adequately varying its diet, as it will not take angel formula or any other gel-cube food. It does eat brine, bloodworms, lettuce, kelp, and hair or macro algae greedily.
My attempts to treat (and prevent the spread of) this malady have consisted of lowering the salinity in my 150 gallon tank, where this fish is kept, to 1.011 SG (this is a fish only tank), and then treating with CopperSafe. Neither seems to have made any difference, and it has not apparently spread to any other fish. The fish is now in isolation, following the bacterial infection noted above.
Is this, as I fear, some sort of parasitic worm? If so, why have lowered salinity and copper not killed it off? Is there some way to eliminate this? Some of the patches are getting pretty bad. One is so inflamed that my wife suggest I remove the 'bumps' with tweezers! I'm really at a loss, and I have never seen anything like this in 10 years of marine fishkeeping.

Question: (follow-up to last month's question about discoloration on head of Juvenile Imperator Angel) Thanks for the information. I have moved forward improving nutrition and water quality. I wonder if you could explain what should happen given all conditions are optimum. I would like to hear what the normal changing process is for an imperator angel. It would give me some insight on what's suppose to happen. Thanks again, your knowledge is appreciated.

Bob's Answer: The adult pattern really entirely supplants (replaces?) the juv. with its concentric blue, black and white flank circles. At first (usually 3-4" total length) the golden lines look wavy, but as the circles go, the line fill in and straighten out. I've seen all this happen in a few months and w/o much change in body length.

Bob's Answer: Hey Jim, thanks for writing so clearly and completely of this malady and your involvement. I too have witnessed similar happenings with large Pomacanthids... and am more or less convinced that the "root" of the occurrence is mainly a-nutritional. There is anecdotal evidence of various vitamins and Iodine lack being a/the causative factor and I encourage you to take a multi-prong attack at making sure these essential inputs are not limiting: I'd utilize a supplement mix (vitamins C, E and A at least) applied to your foods ahead of their being offered and administer Iodine in a useable format as well...
And do look into putting in some live rock (cures many ills along with full-time supplementation of diet) after raising your spg back to something reasonable (1.018-1.021 plus). BTW the Emperor/Imperator gets much larger, to about sixteen inches overall length in the wild, and at least a foot or so in captivity.

Question: Bob, my wife and I have an adolescent Imperator who is suffering lesions induced from poor water quality. We were using a source which contained some metals for about 6 months. We've since switched to a cleaner source and have been using in for the past three to four months. However, over the time we were using the poor water our Imperator developed some severe lesions on and around is facial area. What is the best treatment to help him heal these wounds? We are currently using vitamin supplements with feeding. Also, he has stopped scratching completely since the change to the cleaner water.

Bob's Answer: Do check out that supplement packet and make sure it has boodles of A, C, D vitamins AND useable/assimilable iodine. Additionally, want to give a big plug for TMC (Tropic Marine Center, UK) new carbon product. This stuff is amazing and well worth utilizing for removing phenols, scatols and short chain fatty acids associated with HLLE (Head & Lateral Line Erosion) and general water quality lesions...

Angelfishes for  Marine Aquariums
Diversity, Selection & Care
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by Robert (Bob) Fenner
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