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FAQs about the Koran Angel Behavior

Related Articles: Koran AngelPomacanthus Angels, Marine Angelfishes,

Related FAQs:  Koran Angels, Koran Angel Identification, Koran Angel Compatibility, Koran Angel Selection, Koran Angel Systems, Koran Angel Feeding, Koran Angel Disease, Koran Angel Reproduction, Marine Angelfishes In General, Angelfish ID, Selection, Behavior, Compatibility, Health, Feeding, Disease,   

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

Koran angel, beh., ongoing poor English, non-rdg.       2/9/14
Hey bob,
<... is this a proper noun?>
 question on a particular fish. I have a Koran angel I've had for about a
month or so, 3 inches long, still in juvenile coloration pattern. In the past week or so, I have began to notice a brown coloration across the body.
Its not the whole body, just patches here and there. Almost looks like the algae growth you get on the overflow boxes.
Is this part of the coloration process when it moves to its adult colors, or is this something that needs to be addressed. Appears healthy otherwise, eats Nori, PE Mysis etc. I've searched this, but did not see anything on this.
<Might be normal growth/color change; but perhaps an indication of something amiss water chemistry, nutrition wise. Have you searched re this species on WWM? B>

French Angel question, beh.    3/21/10
Hi, my name is Tom, I have a French angel juvenile, velvet black with great yellow stripes.
The fish is great, eat, behaves like always but 3 days ago it change his color suddenly, looses the black velvet color and it turns into gray, but just into his body, not the fins or the head, they kept black. the fish behave like ever, look great, swims and do the same he always did.
His size is 6 in, is it possible that is changing to adult?
or is something to be cured with medication to get his color back.
please help me.
<Not likely a "disease to be cured w/ medication. Could well be resultant from stress from an aspect of the environment... Chemical, physical, even biological... but you haven't presented any information re any of these>
It has been my fish since October, and when I bought it it was half the size that is now.
he grows very fast.
Thank you.
<Welcome and read here:
and the linked files above. Bob Fenner>

Koran Angel, sick or changing colour   2/26/08 Hello, I must thank you guys for providing such a helpful site, but I cannot seem to find the answer to my problem. I have this Koran angel who is currently in a 10gal quarantine tank. <Mmm, I would be moving this fish> He was in a 75gal with a 2 inch panther grouper, and a Picasso trigger. <Mmm... not very compatible...> Since then his colour has changed from blue to some sort of bleached, white colour. <I see this> We have been feeding him marine flakes, brine shrimp, shrimp, mysids shrimp, squid and mussels. The nitrite is 0.25ppm. <I'd be moving to where this is zero> Could you please help me with this problem? <Environmental... this fish's world is sick, unsuitable. Needs to be in better circumstances... spelled out on WWM. Bob Fenner>

Koran Angle I have a Koran Angle it is about 11/2 in size. I have had it for over 1 year it has started to lose its color on its face how should I treat it >> Really? A Koran (Pomacanthus semicirculatus) that you've had for more than a year... and it's only one and a half inch long?... The color loss is due to either poor water quality, or more likely in your case, to a lack of nutrition... Make sure the fish is getting its share of food, twice daily... and soak/treat the food with a commercial vitamin/iodine prep....  Bob Fenner

Three weeks ago we purchased a Koran angel from a chain pet store, and noticed  that this gorgeous fish was in a 20 gallon tank with four other fish, so we wanted to save it from these horrible conditions. The Koran's juvenile colors were dull, and we assumed that maybe he was beginning to change to his adult colors. But after two days in our tank (65 gallon), his colors became vibrant and he was eating very well. For the past couple of days, the Koran has stopped eating, his colors have become dull once again, he has developed some corrosion around his fins, and his eyes are so glazed they look white. All the levels in the tank seem to be normal, we did just add a sea anemone and two clownfish, but all of them seemed to be coexisting fine. We do not want to lose the Koran, so if you could provide us with any solutions or ideas to what is ailing him it would be appreciated! We do have two invertebrates in the tank, but they can be moved to another tank if necessary (The Koran cannot be moved because of his size in proportion to the other tank). Please respond immediately, we don't want to lose him. >> Unusual... and maybe related to the presence of the anemone... but, if it were me, and especially if I had no other place to move the animal I would leave the Koran in the tank it is now and hope for the best... this species (Pomacanthus semicirculatus) often does seemingly miraculous turn-arounds... Subdue the lighting for the next few days, add a biological cleaner organism if you can (my fave, a Lysmata amboinensis Shrimp) and try to be patient. Bob Fenner, who's article on this favorite Indo-Pacific Angelfish can be found archived at the URL: www.wetwebmedia.com

Angel Questions Hello again, <Cheers, Anthony Calfo in your service> Went to my fish store today looking for a Koran angel and was informed that the juveniles of this and other "changing" species don't change into their adult coloration in captivity. Is this true?  <not true at all... they do change> I've done a lot of looking around on these fish and had never heard that before. They said if you buy one in its juv. coloration it pretty much stays that way. <they are very mistaken> Also, I am following your advice on being able to place a Koran in a 90 fish only tank. I would like to know if it is possible to instead place a small (4") Queen angel in a tank that size in its place. I saw some in the store and find them hard to resist. The store owner said it would not be a problem at all, but thought I would again seek your guidance. Thanks again for your help. Tim <a 90 gallon is hardly a palace for an adult queen or Koran, but admittedly it will work for quite a while. They are great and hardy fishes. best regards, Anthony>

Angelfish Help <<Hi.>> Hi, I'll make this as brief as I can. I've been keeping saltwater for 4 years now. Right now my 1000 gallon has been running for 2 years. The water is great. There's about 700 lbs of live rock, not much life to the rock except a very large Heteractis crispa. It's home to 5 Latezonatus Clowns. For the past two years the fish stock has been the 5 clowns, a juv. Koran Angel bout 5 inch, a 6 in Blue Lined Angel, a 5 in Griffis, a 5 in Scribbled and an 8 in Conspiculatus. 3 Months ago I added 19 Fathead Anthias, all of which have lived. They mostly hide out in a cave in the center of the tank except at feeding times. <<According to Bob, this is pretty normal as these Anthias tend to live under rocks and overhangs in the wild.>> My Koran has been about half changed to adult for about a year now since I got it. How long does the change take? <<Hmm, very good question - I think within a year, but have read several accounts of this process being arrested in captive Korans. Not sure there is any hard science as to why this happens.>> From my pictures it doesn't seem to be changing at all. <<I'm sure with a system of this size and age, that I won't need to go on a long dissertation on nutrition, but what little I've seen about this problem is often anecdotally tied to nutrition; something you might want to consider.>> Also, anytime a fish ventures to the far left of the tank they basically get ravaged by the clowns. Is there anyway to stop this? <<No, they do this in the wild too... "Get away from my anemone.">> My Griffis tail has become a bit raggedy as a result. I'm thinking of putting a divider in until I find a home for the clowns. Any other suggestions? <<No, you have the best solution for that one ;-) >> Thanks <<You are welcome. Cheers, J -- >>

Koran Angel Change of Life Hey again guys. I wonder if you've been asked this before...I couldn't find an answer here. How can I tell if my Koran Angel is in the changing process or if he's sick? The coloration is still bright, but he's starting to look "smudgy." I don't know if this is cause for concern or if it's time for him to go toward his adult coloration. All other fish seem fine. Thanks as always for the input. Matt <Hmm, they do look "smudgy" (muted, lighter toward mid-flanks) as they are changing... If all the other livestock are okay... I'd assume the fish was just undergoing the transformation. Bob Fenner>

Waiting for Change...  3/8/03 I know my tank is overstocked and within the next 6 month I have plans to build a new box that will be about 8 feet by 3 feet by 3 feet or around 300 gallons I think.<538.5 gallons to be exact... A very large but nice tank.  Will be better for you and your aquatic friends.> I do have an oversized sump with an oversized protein skimmer so I am able to keep my water chemistry under control.<Good good good!>  I have had the Koran Angel about a year now... when will it change color?<Adult coloration patterns are attained at a size of six-seven inches plus. Please see here for more info... http://www.wetwebmedia.com/marine/fishes/angels/pomacanthus/koran.htm Hope this helps and good luck!!  Phil>

Hand-caught semicirculatus acting strangely... survival value? G'Day recently i caught a juvenile semicirculatus, about 2cm long (with my bare hands - no net - how clever am i!) and about 2 weeks later noticed it suddenly swimming erratically, almost as though it was paralyzed on one side, swimming towards the surface only to float back to near the bottom, bumped into my anemone twice during this then came to rest on its side on the gravel at the back of the tank - this all took about 1-2minutes. I was sure the fish was toast (despite seeming happy, fed & fat just prior) but gave it a poke - it struggled up and swam feebly to its favourite hiding spot & hovered - 1 minute later was swimming round the tank like nothing happened!!?? ever seen anything like this?? has been a month now and fish is as happy as ever! thanks Jeremy <I have heard and discussed the "acting gimpy" survival value of juvenile fishes with others... as well as the possibility that their "lack of neurological development" at small sizes, early age might account for these seemingly odd episodes... Does seem that "acting odd" might have some survival value... in that predators might not recognize you as a prey item, or de-select you as one unfit to consume. What do you think? Bob Fenner>

Semicirculatus behavior... theories That's an interesting theory - I have a few problems with it though. 1. I chased the fish for 2 hours when catching it and it didn't exhibit this behaviour. 2. As all good fishermen know, an injured fish is a tasty fish (to larger fish) <Not necessarily. I can cite many examples of predators avoiding prey that is exhibiting odd behavior> 3. Swimming into a large anemone can't be pleasant - my fish did it twice in a minute. I'm going to go with the neurological theory. Maybe he had a transient ischemic event or something?? <Perhaps. Bob Fenner>

Angelfish size, age, metamorphosis and tiny stars I have a Koran Angelfish. I have had him for 6 months. He seems to be growing fairly fast. When do they change to the adult color.....is it age or size? <A bit of both... Korans will change at a smaller size as they grow older... or vice versa> He is around 3" now. I also have had little animals that look like star fish. I have had them for 3 years. I keep on getting more and they are increasing in size. The biggest ones are 3/8" . Some have 5 legs and some have 6. The legs seems to get longer as they get bigger. Are they small star fish or is there another animal that is small the looks similar to starfish? <Likely are Seastars of sorts. Please review the Seastar ID sections on WWM re> They are white-cream in color and like to attach themselves to my glass and live rock. Thanks,      Cheryl <Sound like Asterina sp. to me, Bob Fenner>

Kooky Koran Color Change? I was wondering if you could put my mind at rest. <I'll try! Scott F. here today!> I have a Koran angel approximately 4 inches long that has started to appear a little pink. The nearly black/dark blue areas on the fish between the white semi circles appear to be fading and becoming pink all over the fish. The water quality tests for ammonia, nitrite and pH all appear to be fine, as are the other tank mates. The Koran is active and behaving normally and eating well. Is it undergoing the change or should I be concerned? <At this point, I would not be overly concerned, provided that the water conditions and overall health seem to be in order. If the skin appears to be healthy, it may just be a "variation" on the color change process. Keep water quality high, and the feedings up...Observe the fish continuously, and be prepared to take action if it becomes necessary. Good luck! Regards, Scott F.> It is my favorite fish and I wouldn't want anything to happen to it.<With good water, good food, and careful observation, if something DOES happen, you'll be ready to intervene before a problem gets out of hand! Regards, Scott F> 

Penalty box for a rambunctious Koran Angel Hello, My large juvenile Koran has become so intolerant of new additions, I've had to take him out of my 180 gallon tank and place him in the quarantine tank while I acclimate my newbie. In your opinion, what is an adequate time away from the tank before re-introducing him? The tank is mainly aggressive, and he's been in charge for four years. Thanks for your thoughts. Steve <About a week should do it... Bob Fenner> 

Angelfishes for  Marine Aquariums
Diversity, Selection & Care
New eBook on Amazon: Available here
New Print Book on Create Space: Available here

by Robert (Bob) Fenner
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