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FAQs on Aggressive Behavior

Related Articles: Aggressive Behavior, Environmental Disease, Establishing Nutrient Cycling

Related FAQs: Marine Environmental Disease 1, Marine Env. Disease 3, Marine Env. Disease 4, Pop-eye

A huge source of loss, particularly in crowded retail settings, is inter-specific aggression.

Tip For Removing Aggressive Fish? (I have a few for ya) – 02/20/13
Hi all.
<<Hey Tim>>
I have a clownfish, who, after over a year of peaceful coexistence, is suddenly harassing everybody else in the tank,
even including a lovely LPS coral from who it steals food!  I have to net that fish, and I have a tank prepared for it.
But because I have extensive rockwork, with numerous caves, tunnels, and dart-holes, I suspect this will be a difficult task.
<<And likely impossible…>>
Dismantling the rockwork is not an option.
I wonder if any of you experienced pros have any tips.
<<Indeed I do>>
I've begun by trying to get it used to a net, waving the net around harmlessly, but it is very cautious.
<<And much faster and agile than you realize (with all the obstructions available for use during escape) when it comes trying to corral it.  One option is to try to trap it…you can even make your own “minnow trap” style fish trap from a 2-liter plastic soda bottle (see WWM re)…but this often results in quicker/greedier fishes getting caught which can require their removal/holding elsewhere in order to get to the “target” fish.  Another option is one I first tried about 25 years ago…go ‘fishing’ for the little bugger.  Get some very light (2-lb) monofilament fishing line and a very small (size 22) fishhook.  Squeeze the barb down on the hook with pliers…tie it on to the line…bait with a tiny piece of raw shrimp (Mysis- or table-)…and hook the little guy out of the tank.  You’ll want to minimize water movement while doing this to allow better “control” of the baited hook…and keep a wary eye out for other fishes trying to steal the bait.  This doesn’t work for all fishes (e.g. – shy, easily frightened)…but I have removed more than one overly aggressive Damsel Fish in this manner.  I also once removed some very small and quick fishes (Coral Gobies) from my reef tank by building a rudimentary “Slurp Gun”…you can Google this one if you like, but I find the ‘hook’ method to be pretty easy and does little harm, if any, to the fish (is likely less harmful than the stress of being chased about with a net)>>
Thanks in advance for any advice!
<<Happy to share…  Eric Russell>>
Re: Tip For Removing Aggressive Fish? (I have a few for ya) – 02/20/13   

Eric - Thanks!
<<Quite welcome Tim>>
Wow, I never thought about going fishing in my tank!
<<Does work!>>
I may try the trap method first, as this clownfish is by far the most active, greedy, and brave fish in the tank.
If that doesn't work, I'll try the hook, but I'll surely have to wait for a time when my wife isn't around!
<<Good luck!  EricR>>

SW, "Finrot"... aggression, natural, misplaced/crowded fishes...damage, fixing     12/7/10
I have looked through your site and I could not find FAQ's on saltwater fin rot.
<Did you try the search tool with these three words? Put them in here:
and read the cached views. Otherwise, the sections on bacteria and marine disease: http://wetwebmedia.com/infectio.htm
and the linked files above>
I recently bought a Flame Angelfish a week and a half ago. My tomato clownfish was attacking him, and even arranging the aquascape and taking away the item he was hosting did not stop this aggression.
<Not atypical... likely exacerbated by being in too small a volume>
On the second day, I took the clownfish to the LFS. My Flame Angelfish had his back fins (The purple ones) a bit shredded by the clownfish and was scared, but soon after they grew back and he was swimming around normally.
Since he is the biggest fish in the tank, no one is aggressive to him and there have been no fights. He is eating like a pig.
However, a day or two after, the Angelfish's right eye swelled up and now it is huge. I have read on your site that if it is only on one eye, then it is probably mechanical. I suspect the clownfish damaged it while he was trying to attack him. I added 1 tablespoon of Epsom salt to my tank per 10 gallons (55 gallons)
<Too small...>
yesterday to reduce the swelling. I have also been adding garlic Xtreme to his food for the last 4 days.
However, during the course of the last week, I noticed that a while film grew over the Angelfish's pectoral fins. They are now ragged/shredded, and I noticed that this white film has started growing on his tail fin too! Is this fin rot?
<Of a sort...>
Do you think that the Popeye and fin rot(?) have something to do with each other?
<Oh yes. Stress, physical damage...>
I have been changing the water very regularly and the parameters are good.
He is still eating a lot and acting normally.
Will this spread to the other fish? Should I separate him into a hospital tank and treat him with Maracyn 2? If not, what else should I treat him with?
<... No, no, no... and nothing. This fish should be moved/placed elsewhere...>
Thank you,
<Read on. Bob Fenner>
Re Flame Angel... Finrot... BobF needs to find where he placed the prev. corr.  -- 12/08/10

Hi again,
Thanks for the response and for pointing me in the right direction! In your reply, you advised me that "This fish should be moved/placed elsewhere... or alternatively the antagonist/Clown." Maybe I forgot to mention it in the email, but I did give the Clownfish to the LFS on the day after I got the Flame Angel due to the aggression problems. Bye-bye, bully!
<Ah good>
The angelfish is in the tank along with a Melanurus wrasse (Very intelligent and beautiful fish) and a peaceful, small Sixline wrasse that minds his own business. The only inverts I have are 3 hermit crabs and a turbo snail. Nobody has been bothering him since the Clownfish was removed. The Angelfish is still eating voraciously
<A good sign>
(Normal food and nipping at LR) and coloration is bold, has had no fading.
Parameters are: ph 8.2, Ammonia 0, Nitrites 0, Nitrates 10, salinity 1.024 and water temperature is 78 degrees.
I'm fairly certain that his shredded fins and tail are rotting away on their own, not being nipped, since the shredded-ness came right after the white film appeared on his pectoral fins. Yesterday this same film started to appear on his tail fin, and today that looked shredded too.
I was told that this species could be housed in a 30 gallon tank,
<... not so... Please read the article, FAQs on this species posted on WWM>
so I thought that he would do well in the 55 gallon tank. You mentioned that this is too small, I will start to look for a larger tank. (Which I was thinking about getting anyway, bigger tanks are always nicer.) However, the time it takes to purchase/buy/set up/cycle a new tank will be long. I fear that if I do nothing, the Angelfish will pass away during this time.
The fin rot has been looking noticeably worse each day.. I imagine this, combined with the Popeye, is very uncomfortable to him.
I took today off to look through the FAQ's in the Google search. Most of them were on freshwater fin rot (I assume it's more common than in SW?), but this is what I learned:
"Finrot isn't a disease as such; it's what happens when a fish is sufficiently damaged and/or stressed that opportunistic, otherwise harmless, bacteria can breach the fish's normal defenses and cause
"Eventually the bacteria will infect the organs in the body cavity and treatment will most likely be unsuccessful."
So now I understand why you said it won't likely spread to the other fish.
<Not likely no>
The "Understanding Bacterial Disease in Aquarium Fish" article was very helpful, especially since I decided to take Physics in high school instead of Biology or Chemistry. Not a good choice! I now understand the difference between Gram-Positive and Gram-Negative bacteria, and that a Gram-Negative bacteria is most likely causing the fin rot. I think that the stressor that cause the Angelfish's immune system to lower its' defenses was the Clownfish, since the water quality has been fine and he seems to have enough space in the tank, for now. (He is about 3 inches)
<Good size for starting, and for this four foot tank>
I looked for Gram-Negative antibiotics, but there are many!
Which would you recommend? I now have plans to move the angelfish to larger quarters, but I'm afraid that this fin rot will progress and spread to his organs faster than the time it will take me to acquire and setup a larger tank. I think it would be best for me to treat him.
<Again, none... You might want to try boosting the fish's immune system by supplementing its foods... Selcon, MicroVit... HUFAs and Vitamins... this is all I would do. Adding antibiotics to the water is dangerous to all, not likely efficacious... injecting, feeding not likely helpful either>>
Sorry if I went on a rant and thank you for the help,
<No worries. As long as this fish is eating, it is highly likely "on the mend". Be patient. Bob Fenner>

Looks like nipping, Paracanthurus    4/17/10
Thanks for taking the time to analyze and answer my concern. I have a Hippo Tang for about two years and it seems to be getting nipped I can't understand what is nipping her since she is the biggest fish in the tank.
I tried observing her but as you probably know she hides as soon as the lights dim. She eats well and the my Green Chromis, Potters Angel, Banggai Cardinals,
<Any of these could be nipping... the most likely is the Centropyge>
Fire fish pretty much stay out of her way. I have a few Blue Legged Hermit Crabs, I can't understand why she is looking like she is getting nipped at? Here are a few picture
<No pix attached>
 I hope you can give me some ideas as to what may be the culprit.
Carlos Padilla
<Could even be "just chemical/physical. Bob Fenner>

Engineer Goby comp. w/ Clown Tang, Maroon Clown or Blue Jaw Trigger... 2/4/10
Hello everyone at WWM.
I recently acquired a engineer goby from a friend breaking down his tank.
He had him for two plus years in a community tank. After a week in quarantine I added him to my doing he was eating good and showed no signs of disease.
First night in my tank I woke up to my Clown Tang torn to pieces barely alive. I quickly transferred him to my sump I expect him to die shortly.
My first question is could the Goby be the issue or is it more likely to be the Blue Jaw Trigger, also in the tank are a Bi Color Blenny, and a Gold Striped Maroon Clown.
<Either the trigger or clown are much more likely culprits.>
Also is there anything I can do for the clown if he survives these next couple hours (i.e. Additives)?? Thank you in advance for all of your hard work and quick response Michael.
<If he is as torn up as it sounds removal to a QT tank and treatment with a broad spectrum antibiotic may be beneficial.>

Chromis Eat Too Much? Other Fish Don't Get Enough? ...Environmental Problems - 07/08/07 <Greetings Mich here.> I have a 6-month-old 20 gal. marine tank and I'm definitely still in the learning phase. <Yes, hopefully we are all still learning!> After setting up and cycling the tank, I added some live rock, a blue damsel and a striped damsel. The damsels did very well and ate eagerly. I added 2 peppermint shrimp to eat the Aiptasia anemone that had sprung up, and within a few days that was all gone. <Glad to read of your success.> I replaced the damsels with a coral beauty, a Firefish, and more peaceful damsels (3 green Chromis) a few months ago. <In a 20-gallon tank!?!? WAY OVERSTOCKED!!!!> After removing the striped and blue damsels, the shrimp were a lot less intimidated, and are usually out in the open. <OK.> I've since started feeding the shrimp one "crab pellet" each, which they love (they eat it right out of my hand). pH is consistently between 8.2-8.3, but Nitrates have been tough to keep low (they're always between 10-15 ppm), despite feeding only once/day and in small amounts. <That's because this tank is highly overstocked.> In fact, I feed such little amounts and the fish feed so aggressively, I sometimes wonder if they're getting enough! <Possible.> I have a large filter that moves a lot of water (50 gal. model) plus a small power head, but no protein skimmer. <This could help. Regardless, you have too many fish in much to small of a volume!> I need to clean the algae off the tank walls every week. <Likely related to excess nutrients.> I have added a few snails to eat the algae, and they lasted for about 2 months, but eventually died. <Your nitrates are elevated. Environmental issues likely at work here.> Unfortunately, the coral beauty also died within a week of contracting Ich, which it got right after I mistakenly moved around the live rock that was embedded in the sand/gravel during a cleaning. <No, moving rocks did not caused the Ich. Akin to saying you will catch a cold if you go outside with out a coat. The Ich is in you system now. You need another tank, for quarantine/treatment and should allow your main tank to go fallow for 4-6 weeks. More here and the many related links in blue: http://www.wetwebmedia.com/ichart2mar.htm http://www.wetwebmedia.com/ichartmar.htm http://www.wetwebmedia.com/treatmen.htm http://www.wetwebmedia.com/quaranti.htm http://www.wetwebmedia.com/QuarMarFishes.htm > The Firefish survived that OK, but died about 5 weeks later very suddenly (within 12 hours of not looking good, he was gone). The green Chromis have always been total chowhounds. They eat 90% of what I put in (frozen omnivorous, carnivorous, Mysis, etc.). Very little ever got to the coral beauty or the Firefish. <Lack of food was unlikely the issue here, more likely the environmental conditions.> I'd like to put another coral beauty or flame angel in the tank, but I'm worried that the Chromis will continue to dominate the feedings. <You should NOT put a Flame or a Coral Beauty in such a small system, it simply is not big enough.> Should I remove them before adding anything? <You are basically maxed out with the Chromis. I would not add anything more to your system. You have several issues to address. In my opinion it is foolish not to employ a QT tank. You would be wise to invest in a hospital/QT tank. Or use what you have and consider a larger system. You are walking a dangerous line here my friend. Your system is very small. It doesn't sound like you are regularly QTing new livestock, you are overstocking this small system and you could use more knowledge/understanding about disease processes. I encourage you to read, learn and apply what you have learned. Mich>

Aggression in Marine Tank; Overcrowded  - 5/14/07 Hello WWM crew, <Hi.> I have recently added a gold stripe maroon pair to my 55 gallon tank. (other inhabitants include a Kole tang, a valentini puffer, and a couple of damsels I used when cycling the tank,) <...I trust you know there are better ways to cycle your aquarium than with live animals? And personally I don't like to see Kole tangs in anything less than a 75.> my problem is that when I came home today I noticed that the larger clown had some damage to some of its fins, should I presume that this was caused by the puffer <Would be a prime suspect yes...you have a lot of "scrappy" fish in a relatively confined water volume.> and if it was is this normal. <Puffers are notorious fin nippers.> will the clowns damaged fins grow back, <With pristine water quality and a good diet, yes. However, she needs to be separated from the aggressor.> and should I get rid of the puffer. <...If he/she is the aggressor.> also I would like to add a yellow tang to my tank <Too large for your tank, which overcrowded as it is. And you also run into compatibility issues with the Kole tang...which is more confined than it should be as well.> of course this will be after I get rid off the damsels. <Would be a good idea anyway.> would the yellow tang be a problem with these fish. <Yes.> thank you <Adam J.>

Sea star and anemone attacked! Likely not   3/31/07 Hello, <Hi there> I have a 54 gallon corner tank with live sand, ~40 lbs. of live rock and the following inhabitants: A Sailfin blenny, <What species is this? Not the obligate corallivore...> a Firefish, a purple Firefish, <Better to have two of the same species...> 2 Ocellaris clowns, 2 blue-green chromis, a blue devil damsel, 2 blue yellow-tailed damsels, a sand sifting sea star, green bulb anemone, <Entacmaea?> 2 feather dusters, a Scarlet cleaner shrimp, and a blood red fire shrimp.  I added the anemone, sand star, and 2 shrimp about 2 weeks ago.  The tank has been set up for about 6 months and we haven't had any issues.   I awoke this morning to the starfish having one of his legs partially bitten off and something sliced a piece of the anemone's mouth.  I hope that both of them make it through, but I can't figure out who did this. I feed the tank brine shrimp, <Not often I hope/trust> flakes, and sinking pellets daily. <What brand?>   And I also supplement with a few pieces of cooked shrimp <Don't want this to be cooked> 2x a week.  Any ideas about who the attacker would be?   <Don't think there is one here> I thought that maybe it was the fire shrimp because he has a set of pincers????  Please help! Thanks, DP <If there were actual predation going on here... you would see it. You can read re the Systems, Nutrition et al. of the above species on WWM... Please respond to my questions above and re-send. Bob Fenner> Introducing New Fish (Aggression/Compatibility/Quarantine) - 12/16/06 Morning Fsholks (I decided today I would coin a new word:  fishy folks = fsholks). <<Ah, yes indeed…Greetings Dave>> Perhaps I need to take a step back in the hobby and relearn some fundamentals or maybe I have just plain bad luck. <<Rut-Ro…I detect a problem…>> I have 5 fish in a reef tank that I've had for years. <<Ok>> The last fish that I have successfully introduced into my 90 gallon community tank was in 2004 and it was a blue hippo tang, that I killed 5 months ago when I stupidly tried out a buffer agent on my quarantine tank that was holding all of my critters temporarily while I had my 90 gallon altered for a overflow and drain. <<Mmm, yes…not the time to be experimenting>> Since then... scratch one: flame angel, royal Gramma, two purple Firefish, one yellow mimic tang, one Yellowheaded Jawfish, one jeweled damsel, one yellow-tailed blue damsel, and a lawnmower blenny. <<Yikes!  All these introduced/lost within a five month period?>> The flame angel developed pop-eye within two weeks and deteriorated since to his death.  Royal Gramma was found eaten from the tail to the mid body (i.e. only half a fish) ~ I suspect possibly my red brittle starfish. <<Maybe so…but likely consumed the fish "after" it died>> One purple Firefish went into my overflow and never recovered from the pounding water and the suction from the drain... the other Firefish simply died a few days later.  The yellow tang was having his fins picked at by my royal Dottyback and then one day the tang didn't come out from a cave to feed... the next morning he was laying dead on the sand with his eyes missing. <<This Dottyback is likely inflicting physical damage/stress on "all" new introductions, thus causing their demise either directly (maiming/killing) or indirectly (suppression of the immune system leading to contraction of disease)>> Yellowheaded Jawfish was torn to shreds within 20hrs of introduction by my clownfish. <<They "are" damsels you know…>> Jeweled damsel was feeding and seemed healthy for about 2 weeks and then one day didn't come out to feed and the next day was stuck against the powerhead dead.  The lawnmower blenny starved over two weeks and died. <<Some of this seems vaguely familiar...have we danced this dance before?>> Now the latest...a yellow-tailed blue damsel.  I introduced two of these damsels into a 200-gallon tank with fully cured live rock, no traces of ammonia or nitrites, a pH of 8.2, and nitrate reading of 1.7? (Between the lowest and second lowest indicator on a standard Salifert test kit).  I introduced the fish on Sunday Dec 9th and unfortunately suffered a temperature problem thus keeping the temp at 31C for 24hrs...since I have lowered it to 27C. <<Yet another "stress" inducing event>> During the heated water phase the fish were swimming around and didn't seem stressed... hanging out together in what would have seemed a massive tank with extensive rockwork and hiding spots.  I turn my pumps off to feed them allowing the flake to eventually soak and sink towards mid-tank where they hangout in the rockwork, but I have only witnessed one of the two taking a single nip at a piece of flake food...both would ignore an algae pellet, and frozen Mysis shrimp bits. <<Unusual…these fish have proven quite Catholic in their food preferences/tastes in my experience>> All seemed well last night although it seems they have claimed opposite ends of the tank.  On Wed Dec13th, I introduced a 14" Snowflake Moray to the system.  The snowflake never experienced the warmer temperatures.  The damsels came to investigate the eel and didn't seem afraid of him....and the eel seemed disinterested in the damsels. <<Mmm…unless it get s really hungry…but will likely prefer crustaceans if offered>> So all seemed well last night, but this morning one of the damsels was having difficulty swimming at the back corner of the tank.  He had a red rashy type mark in front of his gills, behind his fin, and by where the tail connects to the body. <<Bite marks perhaps?>> At first I thought the gill/fin markings looked like the eel may have clamped down him and then released him. <<My first impression…>> I netted the fish and examined him.  This was not an open flesh wound and the other side of the body looked normal...so I don't think it was an eel bite. <<Still could be "bites" I think.  Not being an "obligate" piscivore, the eel's teeth aren't designed to grab/cut/hold-on to a fish.  Considering the "size" of this eel, I still think it likely tried to eat a sleeping damsel>> Furthermore, just before netting the damsel, the eel was within about 4 inches of a slow moving twitching bite-sized damsel...and completely ignored him. <<Possibly put off by your presence…or maybe hadn't "pinpointed" the fish yet (eyesight is not so good)>> I don't think the eel was involved with the damsel. <<I still am inclined to disagree…Bob, perhaps you could render an opinion?>> <Possibly. RMF> Anyhow, I put the netted damsel into my sump and he immediately gently flowed to the drain and stuck against the sump strainer that outflows to my pump.  I immediately turned the pump off and he tried to swim away... but ended up just floating on the surface of the water facing down or upside down. <<Likely a "goner">> I had no place to put him... figured he was a goner for sure... and ended up flushing him down the toilet. <<Ugh!  Not a good practice…better to euthanize (place in a bag in the freezer) and dispose of in the trash>> My question... damsels are suppose to be the hardiest of marine fish and I have had two that have perished within 2 weeks (if I include the Jeweled). <<Ah, but both were possibly victims of other tank inhabitants (Dottyback for one, eel for the other), in my opinion>> I have one remaining damsel that seems at the moment to be doing ok in with my eel in the 200gallon tank. <<For now>> What happened with the damsel seems to be the same thing that has happened with any Auriga Butterfly fish that I have kept in the past.  After a few days/weeks...troubled swimming...red rashy type marks...and death. <<Hmm…was the eel present?  Perhaps something else is at play here>> I guess in this instance, would you think I am correct in saying that damsels are hardy... but even a hardy specimen with an infection/disease introduced to a temp spike will succumb. <<Stress can manifest symptoms/take down the strongest of us, yes>> Do you think maybe the temp spike triggered some sort of bacteria/disease/infection to infect this fish? <<Is always a possibility>> Is this simply a bacteria picked up from shipping or the store?  A disease? <<I doubt it…the pathogens are always there awaiting an opportunity/conditions to optimize>> Am I having bad luck? <<If water parameters are in-line, along with the fact the other fish are fine which seems to indicate the system is not "poisoned"…I am inclined to think you are having "compatibility" issues>> The markings did not appear to be flesh wounds...or at least not from the eel...I'd figure if the eel bit into him I'd certainly know it. <<Maybe so>> When introducing new fish I float the store bag that is sealed in my tank water to adjust for temperature...15 - 30 min.s.  Then I remove the bag and slowly introduce some tank water in with the store water within the bag.  I either net the fish in the bag or pour the fish from the bag into my net. <<A good/standard process>> I then drop the net in freshwater at a matching temperature to the tank for about 10 seconds.  Is this suitable for a freshwater dip? <<Not really, no>> Your freshwater dip info doesn't say much. <<Really?  I disagree…the info is there for the reading: http://www.wetwebmedia.com/dips_baths.htm >> Is it a quick in and out of the freshwater? <<Depends on the fish…but generally, no>>>> Do I let them swim in the freshwater bucket for 10 seconds?  30 seconds?  Do I keep them in the net and dip them for 10 seconds? 5 minutes???  What kind of time we talking about here??? <<Is explained in the text "unless you've done this a bunch or are using the suggested mellow Methylene blue, stay right there during the process. Your new acquisitions might just hop out onto the floor, you never know. Actually, the only reasonable way to gauge how much may be too much time to spend in the dip is to examine the dipped's behavior. If it becomes erratic (should I offer a definition? Nah!) with thrashing about, inversion, wild attempts at missile-impersonation, time's up." >> Any fish I have dipped seem to be pretty stressed and flip/flop madly as if I was poisoning them. <<Do make sure the dip bath is "both" temperature and pH adjusted>> After the dip (or what I think is a suitable dip)...I lower the net into the tank or QT and let them swim outta the net into the new environment on their own power.  I keep lights off for 24hrs and attempt to feed on the second day. <<An accepted protocol>> I always introduce fish into water that has been tested and considered good to pristine conditions. <<Excellent>> I didn't QT the two damsels or the eel because they were the first and only specimens in my 200gallon tank. <<Ah…but if they require treatment how easy will it be to catch/remove them to quarantine?  And don't forget the extra stressed induced re.  Is usually better to place the fish in quarantine first (Some exceptions do exist) to allow closer observation/provide an environment free from threat/harassing tankmates until the fish has had time to "harden" from its ordeal of initial and recurring capture/transportation>> I currently have a 5" Foxface in QT that I bought two days ago.  I haven't been home to see him when the lights are on...and just introduced some Nori on a clip...will see if he has eaten any of it when I get home from work today. <<This fish will also enjoy some meaty food (Mysis, Spectrum pellets)>> From reading your FAQ's (that suggest not bothering to QT Rabbitfish)...I will introduce the Foxface into the tank, but only after I can confirm he is readily taking a variety of foods willingly.  Sound like a good plan? <<It does, yes>> One comment and question regarding the snowflake eel...it is simply the most magnificent thing I have seen in my aquarium ever...beautiful! <<Amazing creatures indeed>> Feedings…from reading your FAQ's, I will stick feed two to three times a week and alternate between oyster, clam, krill, Mysis, tiger prawns, squid, crab meat, etc. <<Very good>> Question is...how much?  For instance, the eel readily took my first offering of krill, which would appear to be one bite size piece for him.  However, he refused another piece of krill.  Am I correct in saying obviously the one piece was enough...and I should attempt to offer some more food in a couple of days? <<A couple "bite-size" pieces at each feeding should be sufficient>> Some of those tiger prawns are awfully big...I am guessing I only give him a bite-sized piece? <<Yes>> Or until he refuses my offering? <<Overfeeding can reduce this animal's quality of life/life expectancy…best to limit feedings to a couple/few small pieces>> Thanks again! Dave <<Happy to share.  Eric Russell>>

Introducing New Fish (Aggression/Compatibility/Quarantine) - 12/17/06 To clarify from previous email: Within a 5 month period??? Noooo.... these are all fish that have perished within the month of introduction over a 2.5yr period...    <<Ahh...ok>> I wouldn't keep shoving more and more fish into a tank over 5 months... <<Good to hear...>> I space my new additions out by weeks/months.... <<Very good>> To clarify... the jeweled damsel was in my 20-gallon quarantine tank by himself.  When I do water changes on my 90-gallon reef tank (about 10% twice or three times a month), the reef water goes to my 20-gallon quarantine tank... and then the 20-gallon tank water is disposed of during it's 20% weekly water changes (when I have inhabitants in it). <<I see>> With respect to the jeweled damsel, I highly doubt water quality was an issue.  Stays at a constant 26C and 1.025 salinity... no traces of ammonia, nitrite, or nitrates. <<Understood...and you may very well be right...but do be aware there can be water quality issues that transcend the "usual suspects">> The jeweled damsel fed on everything I gave it for two weeks up to the day before he died.  With respect to the Auriga butterfly's... these were among the first inhabitants I had about 4 years ago.  I initially had introduced 3 Aurigas about 4 months after what is now my reef tank had started.  I suspected they perished due to stress... or perhaps nipped at each other.  But that wouldn't really explain how the third one eventually perished the same way. <<Mmm, and impossible for me to say...but sometimes fishes are irreparably damaged during collection/transport in manners that are not visibly or immediately obvious.  Some will even appear to eat/behave normally, yet are still doomed.  And something that has come to mind...have all the "doomed" fishes you have purchased come from the same place?  Something to ponder if so>> At the time, I only had two tiny clowns and a shrimp goby.  Anyhow, your email response has helped. <<I'm not so sure [grin]>> I guess the mystery is still the jeweled damsel that was in my QT tank 2 months ago... and my yellow tailed guy a few nights back. <<If things continue as they have, perhaps you could enlist the aid of a marine biologist from a local university to perform a necropsy.  This may aid in determining what is (or isn't!) mal-affecting these fish>> Anyhow, all seems well in my 200-gallon tank with the eel and remaining damsel. <<Excellent>> One other question... do you still share the opinion that tangs should not be quarantined? <<Mmm, no...quarantine AND freshwater dips (before and after) can prove very beneficial with these fishes.  Many species are very susceptible to protozoan infestations>> I recall when I bought my regal tang years ago, that Bob's website mentioned not to add the additional stress of capture and release twice... and to introduce tang's into the permanent environment?? <<Opinions will vary...but this is one of the "more susceptible" species re Ich infestation...much easier to observe/treat if dipped/placed directly in to quarantine, in my opinion.  And just as important...to be placed in a suitably large/mature system when ready.  Anything less than 125-gallons is "just too small" for this robust and high-strung/twitchy fish.  Regards, EricR>> Pacific Blue Tang Harassed by Resident Wrasse, News at 11 - 10/10/06  Hi all, <Greetings - Emerson with you today.> I have a Blue Hippo Tang in a 110 gallon FOWLR system.  His tankmates are a Sailfin Tang, Volitans Lion, Snowflake Eel, and a Lunare Wrasse.  pH is at 8.2, Ammonia 0, Nitrite 0, Nitrate < 5 usually.  Temperature is about 82, give or take a degree.    <Not enough tank for these fish I'm afraid.> I've had this fish since early June.  He is the most recent addition to the system, the Lunare Wrasse is the second to most recent.    <All quarantined I hope?> I've noticed lately that the Lunare Wrasse has been doing a combination of chasing with the Hippo and sort of "mouthing" his side, at which time he jerks forward a bit and they go their separate ways. I've watched it get worse and worse, until finally on Sunday I removed the wrasse from the system and placed him into a holding tank running off the same filtration system as the main tank.  I suspect that since the Wrasse was the second to last fish established, he is bullying the Hippo out of territoriality, but since the other fish were there first, he doesn't bother them.  I am hoping that by taking the wrasse out for a few days and moving some things around (which I have not done yet) I can break the territoriality and everyone can live peacefully. <Not likely. Of the Thalassoma I have kept and seen these guys are somewhat on and off in terms of aggression. Try a separation period of at least a week. If that doesn't work then either the wrasse or its offending fish needs to go.> Or, would you recommend against this Wrasse with these tankmates?    <Thalassoma wrasse can exist peacefully with most semi-aggressive+ fish without issue given proper settings and placement order. With your stocking list it should have been the last fish added.> The Hippo started flashing repeatedly just prior to the Wrasses' removal, several times per minute against rocks, equipment, substrate, whatever he could find.  In the past, he's done this but never this bad and it's always eventually stopped after a couple days.  Also, he has developed what seem to be scratches, I assume from the flashing (?).    Now that I've removed the Wrasse, I've found that the Hippo seems to be spending more time laying around, sort of half on his side.  True, this is supposedly normal for this species, but I've never observed it in this particular specimen.  Could it be that without the Wrasse chasing him he has move time to, for lack of a better term, "relax," and what I'm seeing with the laying and flashing is actually the first time the fish has had a chance to show "normal behavior?" <It is surely enjoying the lack of harassment, but scratching as you describe is not normal behavior. This is a definite sign of stress.> Furthermore, he seems to always be laying around my large (3" or so) strawberry hermit crab.  I am wondering if he's thinking he's going to get a cleaning (fish are dumb, after all), and this could be an indication of an as-yet-unseen parasite infection?   <Lying and glancing are common behaviors of the Pacific Blue. Due to the stress yours has received you should keep an eye on it for parasites, proper healing of its scratches and general malaise. Don't hesitate to place it in quarantine if you don't notice an improvement in a few days.>   I don't have any other inverts in the system other than 2 of these hermits and a longspine urchin. I know how nervous this species can get, and I am reluctant to remove him from the system for either quarantine or a dip, as I don't want to stress him further (plus he's fast and I'd tear the system apart catching him) so I'd like to get a clearer idea as to whether or not such action is really necessary at this point.   <Which is worse, tearing down the tank to catch a fish or replacing a tank's worth of fish? If only every fish was as easy to catch as my Lunare was. All it took was a dangling krill in one hand and the fish would swim into my other hand, net, Tupperware etc. It would be in the best interest of your tank to trade in either the wrasse or the tang.> He still eats greedily.    <Good to hear! Nori or flake food soaked in Selcon would be a great addition to this fishes diet.> Thanks again guys, <Best of luck Dave!> Dave

Twitching clowns... Lots of cute names... for incompatible, over-stocked, soon-to-be-dead marines. Ho-buoy! Almost past-time to read    10/3/06 Hello Bob I'm a new comer with a query.  I have a small tank of 38 litres, 2.5 kilos of live rock, 1 anemone about 3inches circumference (called Fats), 1 bubble anemone  1 1/2 inches circumference (called Mr. Willys) <Anemones are largely incompatible cross-species... no matter what they're named> 1 star fish (called Miss Movie Star) 1 ocellaris clown (Snoopy 2.5cms long) for this time. but only 2 months ago added  Fats because he never went in to the Mr. Willys). Once I got Fats he seemed happy and complete so after a couple of weeks I added one tiny domino damsel (Spots 1cm long), <Let's call him Mr. Biggee, the Terminator> which he constantly chased around the tank. Snoopy was getting more and more aggressive so I purchased another ocellaris yesterday (Tony - 2.5cm long). <Too much...> Now Tony is the boss of the tank chasing snoopy away from Fats, they locked jaws fighting for the first few hours on off yesterday.  Today doesn't seem as bad but Tony chases Snoopy constantly and they both do this twitching movement on there side (Snoopy does it more)  Tony is forcing Snoopy behind the rock and then returns to Fats only for a few seconds then hangs around Snoopy and back and forth it goes.  Snoopy is a bit ragged today and doesn't look happy. Snoopy tries to return to Fats but Tony is on to him and doesn't let him stay for long and then with the twitching again.  Is Tony going to get him or what's going on. Thanks Terri-Anne <You have too much and incompatible life here... Please read re Anemone Compatibility: http://www.wetwebmedia.com/anemcompfaqs.htm Clownfish Compatibility, Dascyllus Comp.... look these up for yourself. You need to either have a much larger system (tens of times what you have), more systems... or to return some of this livestock. BobF>

- Friends or foes? 7/27/06 - Hello crew!  What a lovely site you have here.  I have a question about the behavior of my 3" or 4" yellow tang and my 2" flame angel.  I have just recently introduced the angel and I have been worried about aggression from either or both of these fish.  I haven't noticed any spurring or fin nipping.  What I have observed is a strange rubbing of faces.  The angel seems to instigate this.  The tang does not seem to mind and will actually follow the angel if he stops and visa-versa.  I'm worried that what seems to be a love connection is actually some type of aggressive behavior. However neither one shows signs of stress. I would really like to know what you think is going on. <It's hard to say for certain. What may seem like possible aggression may just be simple bossy-ness. I'd keep an eye on things to make sure they don't escalate.> Thanks so much!  -Becky <Cheers, J -- >

A Very Aggressive Group!   6/27/06 Hello <Hi there! Scott F. here today>   My question is in regards to the possibility of adding a very expensive Blood Shrimp or Skunk Shrimp to my tank. I'm asking you so that I can avoid feeding my fish a $150 dinner. My fish are incredibly greedy when it's feeding time. I have 4 Clowns, 1 Flame Hawk, 1 Eibli Angel, 1 Singapore Angel in a 90 gallon tank. The Clowns, Hawk, and Eibli even try to eat my finger if I put it in the water near where I feed them! This should give you an idea of how aggressive they are. <That's really rough! I'm not surprised that the Flame Hawk would be somewhat aggressive, but the clownfish being so aggressive is a bit surprising, considering they are in a group. It depends on the species, of course, but you'd think that the aggression would be dispersed among the group. On the other hand, the Eibli can be a rather aggressive Centropyge angelfish.> A few months ago, I added a 3cm long Tiger Blenny, and the moment I released him out of the bag, my fish attacked him and ate him. I was dumbfounded! The main protagonist was the smallest fish in the tank-a 4cm long Clownfish. I don't even think they realize what they are eating. I think it maybe just a competitive thing where whatever is introduced into the tank must be eaten before someone else eats it. <Very possible. Some obvious things to investigate here...How large is your aquarium? In an over-crowded situation, fishes may often display more aggressive behaviour because of the tight quarters and the need to feed competitively. Another obvious question- how often do you feed? Ask yourself if your fishes are truly getting enough food. Another idea: Perhaps it may be time to break up the aquascaping and let the fishes develop new territories and a new social order...Just a thought.> So what is the chance that if i added a small aforementioned shrimp that it would be eaten instantly? <Under the current circumstances, it would be foolish. You need to get a handle on what is causing the aggression in your tank. Again, it could be stress brought about by an aquarium that is too small, or perhaps feeding that is not sufficient. Do ask yourself some focused questions in your search for answers. Are all environmental parameters in check? Stress of all sorts can initiate unusual behaviours in fishes. Go beyond the immediately obvious.> I have read through many FAQs which seem to suggest that the shrimp would be fine with these fish-but I just can't see it happening. <Actually, I would not advise adding a shrimp to this tank simply because of the known predatory nature of the Hawkfish. Shrimp are regularly on the menu for this fish!> Please reply. I don't want to spend this much money on a snack. Thank you. <Agreed- pass on the shrimp> PS- the pale flame hawk is still waiting in the dealer's tank. The poor guy-no one wants him. I wonder why you didn't reply to that question? <Not sure what question you're referring to, but do ask yourself some pointed questions and see if you can get to the bottom of this unusually aggressive crowd. Best of luck! Regards, Scott F.>

Compatibility...Fin Nipping   6/12/06 Dear Mr. Bob Fenner, <James today.> I have quite a problem arising in my 80G tank. I have 1 Clarkii Clown Fish (3.5inch), 1 Thalassoma klunzingeri Wrasse (4inch), 1 Hippo Tang (4inch) and 1 Banner Fish (4inch) and two days ago I added 2 Firefish (2inch). <Tankmates not compatible with the Firefish.  Do much better with less aggressive feeders.> My Firefish are not coming out as they are hiding in the rocks. I see them sometimes but very rarely. When they come out sometimes my other fish chase them away and they again hide in the rocks for hours. What do you think I should do? It's been two days now and I am restless. Do you think with time they'll get use to it? <No, very timid, easily bullied fish.  Suggest you return these as their days are numbered in your system.> Also recently I have seen a lot of fin nipping but I don't know which fish does it but my Wrasse's fins are damaged here and there and mainly the tip of my banner fish's long top fin is pretty much eaten. <Yes, an inviting target.> Yesterday the long fin was only damaged a couple of millimeters but today it's about a centimeter. Who do you think does this? Is it the clown or the Tang? <Mmm, could be more than one, possibly the wrasse and the clown.> Please let me know from your knowledge who you think is the nasty one because then I will remove it immediately. I just can't figure out who it is because everyone is equally behaved when I am around. Please let me know your suggestions. <I suggest you spend some time viewing the tank and witnessing the aggression.  I'd have to guess, and you may be removing the wrong fish in that case.> Thanks so much for all your advices, best regards, <You're welcome.  James (Salty Dog)> Rachel  

Atlantic Tang vs. half black angel  6/5/06 Why would a 2" Atlantic blue tang (Acanthurus coeruleus) pick on a newly introduced  Halfblack angelfish (Centropyge vroliki) that is about 3"? <Not likely in the size/shape system stated below> It darts after the angel and darts away just as quick, but the angel doesn't move....kind of funny.  But, the angel is staying in the top right of my 6' 150 aquarium.  Should I remove it? <... not quite yet> Is it sick?   (looks fine) Will this behavior continue or is this just a peeing contest?  Should I return the 1/2 black?  The angel is picking here and there, but not eating a whole lot and was not interested in the razor Caulerpa and "clipped to the side, but the tang loves it....the little fatty!  Ate a little this morning. I didn't think there was a compatibility problem with the two, though I KNOW the baby Atlantic tang can be a little spit fire when young, but mellow with age.   At the store, they had to take out a yellow tang that was picking on it.   (just FYI) Maybe put the angel in my 29 gallon (has the Caulerpa) until the tang ages a little??? UGH!  Just let me know your thoughts.  Thanks! Carrie :) <... I wouldn't move this/these fish/es. Bob Fenner> Blue Tang Severely Ill...Strategy Suggestions Needed For Removal Of Tang...Input From a WWM Reader  - 05/22/2006 Hey all, I hope I'm not butting in too much here, but I've tried this in numerous tanks and have had great success with it.  Unfortunately it might be too late to help save this guys tang, but it might help others in the future.  First get a large net and stick it in your tank first thing in the morning before the lights come on when all your fish are still asleep.  Leave it there all day and feed as per normal (this is very important....DO NOT MOVE THE NET) I got really lucky one day and had a fish swim right in it during feeding, that made a nice easy catch. The next day get up before your fish do (in other words before the tank lights come on.  Turn another light on in the room your fish will start to wake up slowly, not be moving quite as quickly as usual, makes it easier to catch them.  I've caught I don't know how many fish this way for people I know: at least 7 of the Zebrasoma species, 2 blue hippo tangs, a dragon wrasse, a red Coris wrasse,  a particularly stubborn yellow canary fang blenny, and a terrorizing clown trigger to name some of the more difficult ones I've netted.  It's always worked for me, hopefully it'll work for you. <Thank you for the suggestion, Amanda.  Will post.  James (Salty Dog)> Cheers Amanda Missing fish/inverts   1/18/06 I have a 55 gallon reef tank and lately I keep noticing that about twice a week I lose another fish, shrimp, sea star etc.  They're not just dying, they are completely gone.  My tank is about three years old and until recently I have had no problems.  I've check all the standard tests and all level are good. <What could this mean?>   Lately over the last month or so I have lost a 4" Anthias, a cleaner shrimp, a banded coral shrimp, a bi-color blenny, 2 peppermint shrimp, 2 yellow clown gobies, brittle star (his legs where chewed off right to his body) <Mmm, a possible clue> and my serpent star is alive but has had good chunks of his legs chewed off. I try to research each fish or critter before adding it to my tank.  Can you please take a look at the list of thing I have in my tank and tell me if you think one of these current occupants could be the potential "night stalker" Coral Beauty tri-colored wrasse maroon clown lawn mower blenny 2- blue green Chromis pistol shrimp <Might be this...> serpent star <Not an Ophiarachna I hope/trust> pencil urchin sally light foot crab various leather corals and mushrooms Hawaiian fan worm snails and small hermit crabs Any ideas, I want to get what ever is doing this out of my tank before I have nothing left.  I would appreciate any input you could give me. Thanks Nikki <Mmm, you could have a Mantis... possibly a killer species/size predatory worm... I would try baiting it out... toward night time, with a flashlight to check, a ready net to try catching/removing. Bob Fenner>

Aggression…compatibility, Aiptasia, overcrowding and nutrient issues  12/20/2005 Great Site, <Thank you.> I have a 90g reef tank that has been running for about a year and have recently encountered Aiptasia. Based on research I added a Copperband.  I already had an Indian Ocean Sailfin in the tank since startup.  In addition to the Sailfin, I have a Foxface, Blue Hippo, Anthias, Orange Spotted Goby and a Firefish. <VERY heavy stocking load for this size tank, the two tangs each reach around 12" length as adults. (The Sailfin more around 18").> The problem is since introducing the Copperband a day ago, the Sailfin has constantly been chasing it around the tank and will not let it out of the corner of the tank. <Honestly I'm not surprised. Sailfins and Zebrasoma tangs in general can be quite territorial especially to new additions and conspecifics (look a-likes).> The Copperband is eating which is great, but I have to feed it with a turkey baster behind the rocks otherwise the Sailfin attacks it.  The question is should I remove the Copperband or is this just a temporary issue and will resolve itself over time without death?   <This issue will not resolve in time, it will only get worse until ultimately; yes a death occurs. Furthermore both tangs will eventually grow to large for this tank…at this point it is already physically/psychologically overcrowded. There is also a chance this overcrowding ties directly into your original problem with the nuisance anemones, overcrowding leads to nutrient problems which is usually the root cause of proliferating Aiptasia.  Adding a fish to destroy the Aiptasia only rids you of the symptoms and not the problem. Adam J.>

Filter Question  11/22/05 Hi, <Hello there> How are you. First, I would like to thank you in advance for any help, and also for all of the amazing support and info in general you guys provide. <Welcome> I recently upgraded from a 20 High that was running a Fluval 104 to a 30 Long. The 30 gallon tank came with an AquaClear 70, so I decided to use both filters. The two filters are on opposite corners. Both filters are tri-media (foam, carbon, ChemiPure). I have around 15 pounds of live sand and a few manmade fish "homes".  Fish include 2 Perculas (1 inch), 1 clarkii (1 inch), 1 velvet damsel (1 inch), 2 three stripe damsels (1/2 inch), 1 yellow stripe maroon clown (2 1/2 inches), and 1 yellow tang (2 inch diameter). <... this is way too much incompatible life for this volume> There is very strong water movement that is being created by the 2 filters, and my concern is that it is disturbing the fish. <Mmm, no> When watching them at night, my impression is that they are having trouble finding calm regions to settle down in and sleep. <Likely just reacting to each others presence> Another problem is that the heavy water movement is making feeding difficult. The food is blown away too quickly before the fish can get to it. My main question is, how much is too much? Is one filter more than enough, and if yes, should I stick with the Fluval or the AquaClear? <Not a problem with the filters, water movement. There is much more in the wild> I thank you very much for your help. I have recently become addicted to the aquarium hobby. I started with a 10G freshwater, then added 3G and 5G Eclipse tanks, then a 20G freshwater, then the 20G saltwater, and finally the 30G saltwater. And this is all in the past several months! I love my fish and I love the hobby. Thanks you! <I do hope you will continue in/with it... but you need to address the crowding here... and quickly. Please read on WWM re the system requirements and compatibility of the species you list above... Bob Fenner>

Tang Injured  11/19/05 Hi, Can you please offer some advise for my Powder Brown Tang. Last night it was  bitten by my Stars and Stripes Puffer who is much larger. They both went for the same piece of food and the Tang was bitten in the mouth. Its mouth appears to be pushed over the side and deformed and bloody. <Not good> He immediately went to the back of the tank. This morning I put some flake in and he tried to eat but his mouth does not open nor is normal. It is pushed over to the side. Is there anything that can be done to save my Tang? Please help.  Thanks... Sherry <Not likely anything can be done... other than wait, hope for some "miracle" self-cure. Bob Fenner> 

Sudden problem in stable system  11/15/05 Hello to the WWM crew! <Glenn> Several days ago I noticed several patches of white material or coating on my Coral Beauty on the top of its head and surrounding areas. The fish was behaving normally, but it looked a little "beat up" and did have a piece missing from its tail, <Good descriptions> which I assumed was the result of a run in with the Yellow Tang. The white areas disappeared over the course of a day or so, and the fish's behavior remained normal. I assumed it was sand from the bottom of the tank acquired while fighting or fleeing.  <Mmm, not likely> Today the fish is swimming erratically with seeming loss of all equilibrium. It attempts to swim, but only manages to move in a corkscrew pattern.  Breathing is normal, but it's dorsal and anal fins and tail are now more tattered.  (Possibly more mistreatment from tank mates?) <Possibly> It's color is a little abnormal and seems to be mottled in areas around its head, but the abnormality is not pronounced.  I do not suspect any parasitic disease as this fish was in a completely stable tank with absolutely no additions for nearly two years, the last being this Coral Beauty. All livestock in the tank were religiously QT'd for 6 weeks.  Tank parameters are 75g FOWLR 80 deg F amm. 0 nitrite 0 nitrate  0-barely readable pH 8.3 SG 1.0235. What other possible causes are there for this?  <Internal complaints, genetic or pathogenic...> I was thinking POSSIBLY that since it had the patch of white (sand?) on its head that it might have slammed into something in the tank while escaping the Tang resulting in brain damage, but I would assume the swimming problems would have been immediate.  <Not necessarily> I am perplexed, since I follow excellent tank management procedures, and am particularly careful, (some might say obsessive), about QT. The other fish in the tank show no signs of any disease or any other problems. I have removed the Coral Beauty to a hospital tank with antibiotics as a precaution, but am unsure about any other treatment. Any help, suggestions or insight would be most welcomed.  Sincerely, Glenn Brookes "Bladuser" on WWM <I do suspect (as you seem to) some sort of altercation... with the Yellow Tang... a swipe of the scalpel will do it... Bob Fenner> 

Frustrated with disappearances 10/25/05 Good morning.  <And to you>  I'm a new hobbyist, and have learned a great deal from your website, but was wondering if you could help me with a frustrating problem. I've followed lots of advice from your site, and after about 6 weeks, I have the beginnings of some nice coralline growth on my live rock. My problem is disappearing bottom feeders, specifically a 3.5 inch algae blenny about two weeks ago (never found a trace, in spite of moving around rocks), and now a new 3.5 inch sand-sifting orange spot goby who looked great sifting my sand bed yesterday, and then just vanished. It's only been a day, but I fear the worst.  I have a 36 gallon bowfront, 4" deep sand bed (Caribbean play sand), 10 pounds base lace rock, 40 pounds mixed Florida and Fiji live rock, 2 internal powerheads, hang-on Prizm skimmer, hang-on filter (for intermittent charcoal and mechanical filtration), 2 65Watt power compact lights. Ammonia, nitrites, nitrates undetectable. pH is 8.2 and temp steady around 80. Occupants are 2 true percula clowns, one small coral beauty angel, 1 brittle star (definitely not green), 1 common cleaner shrimp, 8 blue leg hermits, 3 red leg hermits, 5 Astrea snails, 5 Nassarius snails, and 2 small emerald crabs (roughly ?" across the shell).  After reading your site, my suspects are: 1: hidden predator (unseen Mantis despite prevention attempts, and not seeing anything staying up to watch at night) or... 2: the emeralds. 3: brittle star. I was hoping you could help with my suspect list, and advice/course of action to find the culprit. I'd be surprised to hear the emeralds or brittle star are at fault given the size of them in relation to the missing fish, but I'll defer to your experience. I would really like to get on small bottom fish (preferably a goby or Jawfish), but I'm frustrated with the losses (and the cost), so I don't want to add anything else until I've sorted it out. I don't want to remove all the rock, so my thought was to proceed with some sort of trap at night. I'd love to tap your experience on: 1: Am I on the right track in assuming I've got a mantis, or would you suspect another culprit? 2: How common are mantis shrimp? I've read about them at your site, but everybody at the LFS said they had never even seen a mantis shrimp. How unlucky could I be with such a relatively small amount of rock? 3: What to do about it... I've considered fashioning some type of trap and baiting with shrimp, but I'd like you advice on where to place it and what to bait it with. With the type of fish disappearing, I'm unsure whether to trap near the rock, or along the sandbed in the front. If there's a bad guy in there, I suspect he's buried in the rock, and traps the fish when they are either sleeping or foraging deep in the rock. I've had no trouble (at least not yet) with the coral beauty, or the clowns. Thanks for a great site!!!! I'm loving the hobby so far, but this particular frustration is really giving me a fit (and my little boy gets really upset when we lose a fish).... <Unless the brittle star is fairly large, it doesn't appear you have any threat to your fish. Getting mantis shrimp as hitchhikers in live rock isn't that uncommon. Do you ever hear any clicking sounds at night? Are you sure the fish aren't in a overflow box etc? Did you check the floor behind the tank? If everything is OK in that regard, I'd probably get a mantis trap and bait it with some frozen type of food. The orange spotted gobies do best with a live sand bed and frequent feedings. Quite possible he wasn't getting enough food and may be dead and buried in the sand bed. Try stirring up the sand and see if that isn't the case. James (Salty Dog)> 

Community tank not so friendly 10/12/05 Afternoon fellas... <Mike G with you this evening.> Two things: First of all, I had emailed you about a month or so ago about the burgundy felt-like carpety algae growing over EVERYTHING in my tank... I increased my water flow rate in my tank from about 8 times/hour to 20 times/hour (a MaxiJet 900, a 1200, and a Rio powerhead that does 1100gal/hour).  <Good move.> I've also trashed my SeaClone Protein Skimmer (what a piece of......) <I agree wholeheartedly.> and replaced it with an Aqua-C Remora Pro with the Mag-3 pump.  <Very nice.> I am now getting almost a full cup of solid foam gunk every two days vs. every month or so.  <Yum.> Furthermore, these problematic algae/bacteria growths are starting to break down. They are turning from burgundy to greyish... and retreating/flaking off all of my live rock in some areas.  <Good to hear!> I'm assuming that HOPEFULLY in a few more weeks that the algae will be totally gone.  <Sounds like it.> Second note... my community tank has turned into a bloodbath!  <That's always fun.> Last weekend I introduced a Yellowheaded Jawfish and a fire shrimp to my 90 gallon tank that also contains: 2 Perculas Clowns 1 Yellow Watchman Goby 1 Royal Dottyback 1 3" Regal Tang 1 larger Coral Banded Shrimp Sandsifting star Small banded serpent star Larger red brittle star Assortment of small hermits and two larger turbo snails. I have not had any tank fatalities in over a year, aside from one starving lawnmower blenny.  <Starvation and Derasa Clams always seem to get those little buggers.> My two turbo snails have been around for a couple of months. Last week one of the snails was sitting in the large brittle star's lair. I did notice the star had an arm or two wrapped around the snail and there were a few hermits in the area. Anyhow, my $6 snail is dead.  Not sure if the star had anything to do with it?  <Maybe, though I've never ever heard of a star going for a snail.> I'm thinking the hermits were cleaning up his body.  <Some hermits will flip, clean, and commandeer snails. That is, topple them and eat their soft, exposed bodies, then steal their shells. You'd need one large hermit to accomplish that feat, however.> Same weekend I introduced the 3" long Yellowheaded Jawfish. I kept the lights off for a day. I did notice some bottom activity where the Yellow Watchman Goby was doing the mouth-open head-shaking intimidation thing... the Jawfish relocated. The next day, the Jawfish's body was being ripped apart by my larger Percula. Not sure if he was already dead and being eaten... or if the Clown attacked him.   <I pick choice A. Probably just didn't settle in well, perished. Clown got an easy meal.> It did appear that the clown was not eating... but simply just attacking the carcass.  <Probably attempting to rip off bite-sized chunks of Jawfish.> The Dottyback was also hovering, but I can't say for certain if he had any involvement.  <Doubtful.> My smaller Percula wasn't involved.  <I don't think any of your fish was.> This all took place within 18 hrs of the Jawfish's arrival.  <New fish syndrome... some fish just don't acclimate, usually the ones you've waited a while/paid a bundle for.> I also had my Fireshrimp introduced at the same time last weekend. The Fireshrimp has remained hidden at all times... doesn't even come out to feed from what I can see.  <Give it another week. Sometime they'll take a bit to acclimate fully.> For the past day or two the larger brittlestar has been hanging out in the same area as the Fireshrimp. Last night, I noticed the Dottyback having an intense interest in the back corner where the star and shrimp were hanging out.  <Some Basslets will consume ornamental shrimps... Royal usually do not, but it's not unheard of.> I went up to the tank and saw two of the arms constricting the shrimp who was fighting like mad to get away.  <Might be time to relocate the star. Suspect in the murder of an innocent snail, attempted murder of Fireshrimp. How does one fingerprint an echinoderm?> Just as I was about to interrupt the fight with tank tongs... the Dottyback darted in and took a chunk out of the fire shrimp's midsection.  <Aha! An accomplice!> The tank tongs scared away the Dottyback and by gently gripping the large brittlestar he let go of the shrimp who scurried away.  <I have to give you one for patience. I'd not be gently gripping the star at this time. He'd be lucky to escape with 4 arms if he attacked a $40 fire shrimp.> While putting down the tank tongs and grabbing my net the Coral Banded Shrimp already had the Fireshrimp in his pinchers.  <Bad day for the fire shrimp, I take it?> I also fended off the CBS and rescued the Fireshrimp who survived in my already running quarantine tank for only a few hours. The salinity, temperature, everything is a pretty good match to my main system. When I confirmed my Fire shrimp's death... I put him back into my main tank where the CBS feasted. <Nothing like a reward.> I have been reducing my feeding to help with my algae problem... but in my opinion I am feeding enough. I am alternating between flake, frozen brine that is thawed, frozen krill that has been thawed, and algae disks or dried seaweed.   <Sounds fine.> Everyone seems to be well-fed and everyone but the newcomers fed. <Did they have a chance?> What's the deal?  <You have some bad apples on your hands.> I'm afraid to introduce ANYTHING new into my tank. I did want to add a Foxface in the next few months... but I fear that my larger Percula and/or Dottyback will end up stung from the Foxface since the clown seems highly aggressive.  <Female?> If I do get a Foxface, do you advise getting a specimen that is larger than my clown so that the other fish will be a little intimidated?  <I do.> Do you think my tankmates have become too used to each other and very territorial to newcomers?  <Possibly. I think you need to get rid of that star. Seriously.> I did rearrange my rockwork about 3 weeks ago... I am a little concerned also about my larger star... I do realize that there was only one way out of the nook that my Fireshrimp was hiding in... a perfect ambush for the starfish. I'm hoping that was a chance opportunity of nature.  <That's exactly what the star relies on for food. Chance.> Any thoughts? Advice? $86 and less two creatures a week later... not a happy camper. <I'd hate to be either of the purchases, as well. Best of luck. Mike G> 

Aggression and Compatibility  9/24/05 <Adam J with you.> Two quick questions.   <Ok go for it.> We've got a 120 Gal FOWLR with a purple tang, dwarf zebra lion, H. ornatissimus wrasse, Forcipiger BF, and three or four small asst. damsels.  Water parameters are great.  The issue is between the purple tang and the BF.  They got along great when they were introduced.  About a week or two later, the tang started following around the BF and occasionally nipping. <The purple tang and others in the Zebrasoma genus can be quite territorial.> This calmed down quite a bit in a day or two.  That was a few weeks ago.  All of a sudden, I noticed this morning that most of the BF's beautiful tail was shredded!  Must have been the tang -- it was also suddenly chasing around the damsels, too (never seen that before).  Could it just be hungry?  It attacked the Nori I put in, and seemed to calm down a bit.  Any suggestions?  We love that tang. <There are many methods suggested to quell fighting amongst tank mates, and you can find those here on the FAQ's at WWM, my favorite one is rearranging rockwork and thus creating a new territory. However these methods are still not guaranteed and it may be necessary to remove the victim or aggressor permanently.> Also, I was wondering if Talbot's damsel was "calm" enough to keep with two clown gobies (yellow and green) in an 11 gal nano reef (15 lbs of live rock, lots of hiding places).  I had a C. hemicyanea in They're previously, and had to remove it because it made the gobies "nervous".  Sounds like Talbot's is a more placid fish. <They are much more social than most of their Damsel cousins, however they too can be quite territorial at times. To increase your chances of pulling this off I would add the gobies first (if you don't already have them) allow them get established before adding the damsel.> Thanks, Dan <Anytime, Adam J.> Socially and Physically Overcrowded  9/22/05 Hello WWM Crew! <Hello Adam J with you.> First let me say thank you to all of you for so selflessly devoting your time to helping others with this wonderful hobby.  If you'd been around in 1998, I might not have taken a 6 year frustration hiatus from the hobby. Information (knowledge) is king in this lifestyle of ours. <Seems like a lot of us went through those "newbie" woes.> I have a question regarding some pretty strange behavior that my blue hippo tang, Dora, has been exhibiting.  First, let me start with the basics.  FOWLR 60 gallon tank (soon to be 150) with a 29 gallon refuge. <Good move on the upgrade, you'll need it with the potential size of your current stock.> Water tests just fine, and not of much pertinence to this question, I believe.  I have the aforementioned blue hippo (about 5"), a porcupine puffer (4"), three stripe damsel, yellow-tail damsel, and bluefin damsel (1").  Everything was fine.  All the fish got along great.  Then, on a trip to the LFS, I found a fish that I originally was going to purchase after setting up the 150, but it was the right size and price, so I figured (perhaps incorrectly in hindsight) that it would be fine for a month or so.  I bought a 1" or so Humu Humu.  I acclimated and added him (still working on the quarantine) and all was great. <I would have waited on the Humu-Humu.>   But then, my blue hippo (Dora) started attacking the puffer???.  She has consumed about half of his tail and harasses him regularly at this point.  I originally suspected the Humu, but the puffer reacts to Dora by turning around every time that Dora comes close....no reaction to the Humu.  Then, I saw it! She went up and nipped at him.  So here are the questions:  What would cause the  blue hippo to start attacking an existing fish upon the introduction of a new fish....is this territorial, food competition, or something that I don't understand? <Fish are interesting creatures that form structured social hierarchies, it appears the new fish may have disrupted this.  While Hippo Tangs (Hepatus Paracanthurus) tend to be mellow, you have to remember they are still in the surgeon fish family and still very capable of aggression (those scalpel aren't just for show).> And secondly, what can be done to stop it? <Well I would first move the puffer or the Tang into QT to allow the puffer to recover, I imagine he is very stressed out from this harassment. And unfortunately I would also consider permanent separation of the two, preferably removing the aggressor.>   I love both Dora and Puff - they are like family to us and would hate to part with either.  Will the 150 gallon tank fix the problem? <More room will definitely help the situation, though there is still no guarantee.> I  remember reading that removing the aggressor and rearranging the live rock will sometimes erase or diminish feelings of territoriality, but what about just removing the blue hippo to a quarantine without rearranging the live rock - will that likely produce any change? <All of these solutions can possibly quell the fighting but it is still a gamble.> How long should the aggressor be removed? <Until the victims have fully recovered and have resumed normal behavior, but permanent removal is often necessary.> Any help would be greatly appreciated...I hate seeing my Puff's tail disappear. <I understand, no one likes to see their livestock in distress.> Thanks again, and keep up the great work! <Anytime, Adam J> Territory...Not Enough - 09/12/05 Hi guy's you helped me before I thought I'd try again. <<Alrighty>> I recently added 2 small blue tangs, and 1 small Koran to my tank. <<This doesn't sound good.>> My three stripped damsel is very unhappy about it, he keeps ramming the tangs, and chasing the Koran, though when ever it comes close the Koran swims sideways and the damsel leaves it alone.  What do you recommend I do? <<Return the tangs and angelfish.>> Will the damsel get used to the newcomers? <<Probably not before it kills one or more.  Unless this system is more than 6 feet in length and of several hundred gallons in volume your newcomers are doomed to a life of developmental retardation...if the damsel doesn't kill them first... EricR>>

Royal Gramma aggression against Pacific Blue Tang 8/11/05 Good morning WWM Crew! <Hi there, Leslie here for the crew this evening> A bit of background:  I have the royal Gramma who wasn't doing so well in the QT. You suggested adding an air stone and he perked up over night!   <Glad to hear that worked for you and that the fish is doing well.> A week later I added him to the main tank.  I also had a 2 inch Pacific Blue Tang in a QT (different tank) which I added to the display tank last night.  The Royal Gramma immediately started posturing at the poor fellow.  I let him posture thinking he'd settle down, but after ten minutes of that I actually saw him take a nip at his flank. <Ak, bummer> I turned the lights off and everyone went to their respective "corners" and the tang found a cave in which to settle down for the night.  I realized this morning (albeit a bit belatedly) that I hadn't rearranged the rocks to confuse everyone. <Woops, its never to late!> Display Tank parameters: 90 gal MegaFlow All-Glass aquarium (48"L x 18"W x 24"H) single strip 40 watt light so far (upgrading fixture in a few months for corals) 23 gal sump w/Mag-7 for return Aqua-C Urchin Protein Skimmer closed loop manifold with Mag24 2 - 600gph powerheads in opposite corners 120 lbs live rock 120 lbs live sand (4" DSB) Temperature:  80 degrees Fahrenheit pH: 8.1 salinity: 1.023 Ammonia:  0 Nitrite:  0 Nitrate:  10 - 20 (hard to tell with the strips) 2 - A. percula clowns (mated pair, 1 is 1 1/4", 1 is 2") 1 - Brown Striped goby (3 1/2") 1 - Lawnmower Blenny (3") 1 - Royal Gramma (2 inch) 1 - Pacific Blue Tang (2") The tang is the last fish I am planning to add.  My question:  is it too late to rearrange the rockwork to help the Tang settle in better without the Gramma's aggression issues?   <Nope, not at all.> Should I simply allow them to figure it out for themselves (not sure I like that idea).   <I am not fond of that idea either.> I'm tempted to remove the Gramma (though I'm not looking forward to the chase) and put him in solitary confinement in QT for a week to let the tang settle in better before adding him back. <This is actually a pretty good idea. However you are right the chase will not be fun and can be stressful on the inhabitants. The times I have had to remove fast moving trouble makers, I opted for removing all the rock. Although a big and messy a project, I find it less stressful on the fish. You may want to consider this as long as you are planning to rearrange the rock.> Your thoughts or suggestions would be most helpful.  Thank you. <Your most welcome, Leslie>

Missing Fish 7/20/05 Hi gang, John here. If you are a fan of the CSI television series, you may like this one. <Am "forced" to watch such shows... semi-continuously... am thinking of applying some of what I've learned...> I came home from a weekend trip this past Sunday to find 3 green Chromis, a cherub angel, and a hippo tang (3.5") missing from my 90 gallon, non-sumped reef.  All were in there for at least five months save the hippo who was put in last Wednesday after a four week quarantine, and all appeared healthy the previous Thursday.  The other tank residents are a yellow tail blue damsel, 2 ocellaris clowns, and a yellow tang (4"), and a number of corals, and other invertebrates, all of which are okay except the tang who appeared ill but has since recovered.  Water testing showed nitrate, nitrite, and ammonia to be nil, and pH about 8.4.  Water temperature was up to about 84F due to the current heat wave.   So, I did a 20% water change and inspected every piece of rock, removing most of the rock to quarantine, expecting to find their little corpses (there was nothing stuck on the various pump suctions).  I found not a trace nor did I find a mystery predator. Question is, how is it possible for five apparently healthy fish to perish and leave no remains in the span of less than four days? JT <Is possible... that they died... or were helped in that regard (predaceous crustaceans, worms...) and decomposed this quickly... Is there a chance that a biped thief made off with them? Bob Fenner>

Damselfish, (actually aquarist) Problems 29 Jun 2005 Hi, I got a saltwater tank about two weeks ago and started off with a yellow-tailed damselfish. <You placed a Damsel in an uncycled tank...> My tank is 30 gallons and shaped like a cube (with not a lot of surface area). For decoration and hiding places I have a conch shell and large rocks. I'm assuming that you get a lot of questions about angry damselfish and I've read through most of them... but they didn't really answer my question. A few days after I got my tank, I added a coral banded shrimp <Not a good idea to add invertebrates into uncycled systems> and the damselfish seemed to get along fine with him.. but after I added a second yellow-tailed damselfish and a neon goby my original damselfish went crazy. It uses its fin to push the other damselfish away and chases everybody out of its territory (the rocks) <This tank is too small...> It even began bothering the coral banded shrimp, which spends most of its time in the conch. And now my shrimp seems fed up with my damselfish and has begun trying to attack it back. Although you've mentioned repeatedly that the aggressive damselfish should be removed, I was wondering if it would be alright to wait it out and see if my angry damselfish will calm down and become friendlier, instead of having to just remove it. I don't really like the idea of having just one damselfish because... I "want it to have friends". Is there anyway I can achieve harmony in my tank without having to remove my first damselfish? Thank you! <Mmm, not waiting till your tank was established is a mistake, and has contributed to the aggression you list. Please read here: http://www.wetwebmedia.com/estbiofiltmar.htm and on to the linked files above, then over to Damsel Compatibility, Systems... Bob Fenner> Disappearing fish Hi WWM Crew, <Brian>             I have/had a Hi-fin banded goby that I had for 2 months that was eating fine, had a burrow at the front of the tank and was extremely active. This morning I woke up and he wasn't there staring back at me when I looked in the tank. I thought nothing of it, but when I fed later that day he still was not out. I started worrying a little but then my Sixline wrasse picked at a piece of LR and out floats a very clean skeleton of my goby. I was sure this was my lost fish because whatever had gotten to it left the last band closest to the tail. I don't think it just died because it seemed very healthy, and even if it did, I don't think it could decay that fast. <Fishes can, do> I am very concerned because I don't want what ever did this to wipe out the rest of my livestock. PLEASE HELP! Brian <Help with...? You may have a predator at play... a crab, other crustacean... predatory brittlestar/s... or just opportunistic "cleaner uppers"... Careful observation is what you need here now. Bob Fenner> Re: Disappearing fish Thanks for the speedy response, I did just see a crab that must have come in on the live rock. How should I get rid of it at this point. I've seen the Mantis Shrimp traps but the LFS says they don't work  very well. It is just a small crab, tan, the legs are about 1 in. in diameter. Any suggestions would be greatly appreciated. Brian <Please see WWM re these animal groups... there are a few ways to tempt, remove them. Even small species, specimens can be surprisingly predaceous. Bob Fenner> New fish being killed I have a 125 gallon salt water reef aquarium. The current inhabitants are a Niger Trigger, Royal Grammar, Yellow Tang, Blue Tang, Six Line Wrasse, Maroon Clown, 2 blue Damsels, Lawnmower Blenny and a Watchman Goby. Most of the fish have been together for a year except for the lawnmower blenny.  In the past two months I have had 2 mandarin gobies killed, their scales were completely missing. A Scooter blenny and lawnmower blenny killed. The past two weeks I have had two Coral Beauty Angelfish killed. I have removed a large Emerald Crab, Domino Damsel, Scopes Tang and a Coral Banded Shrimp. I have also added more live rock. When I introduced my last Coral Beauty I had all of the lights off for the night. I saw him alive the next morning. Later that day with the lights on I noticed a mark on its side and noticed the fish not eating with the others. Today I found him dead. The only fish that has survived more than a week is this latest lawnmower blenny. The previous one was being picked on by the six line wrasse. I then purchased more live rock. I am frustrated removing my current animals and having new ones killed in a day or two. I do not hear and clicking noises that mantis shrimp make. My fish store does not know who it might be killing the fish. Any ideas? <No, not really. The maroon clowns can become nasty. James (Salty Dog)>  <BRITTLE STAR! Would explain a lot, my friend.>

Injured Fish Follow up MacL <Nice to hear from you again Amy and of course Mimosa!> Your advice saved a life!  <I am so glad to hear that. You have frankly made my day.>  I may be a bit premature but I think my damsel fish is going to make it! He had been in the fight if you remember..  <I do>  I put Mimosa (the fishy) in the QT tank and put in some erythromycin (sp?) just to be safe. This morning his color was really faded and he was splotchy looking. However, when I got home from work today he was swimming around, his mouth was closed, and his color had returned. That's the Mimosa we know and love! His injury site still looks a bit sketchy but I have hope that he will have a full recovery.  <I would keep him separated until he totally heals.>  I would like to pester you with another question though, once he heals what shall I do? If I move the rocks around do you think all will be well?  <Generally if you disturb the territory it will help the fighting to some degree. Occasionally it will stop it totally.>  Or will he never be able to return to the main tank? Will the attacker go after him again? I have 2 suspects, do you think it would be the Bicolor Angel (these two fight a lot!) or the Orangespotted Sleeper Goby (these 2 also fight quite a bit), which would you suspect? The other fish are all really docile.  <I understand but its also possible that one of the docile fish got fed up and fought back. I really think once you get him healed up you'll need to totally rearrange things. If you put him back in and there is fighting that resumes it would be best to take him out.> Thanks again for your help and time! <I never give up on a fish, they can do amazing things. Good luck to the both of you. MacL>

Injured Gramma >Good evening Crew. >>Good morning, Marina today. >I need some advice, please. >>My pleasure. >I purchased a Royal Gramma on October 16.  Put her through a "freshwater" dip, then 21 days of quarantine.   >>A note - best qt protocol is 30 days minimum, disease free. >I moved her from the QT to my display tank on Sunday, Nov. 7.  She was fine and energetic.  I have some Yellow Tail Damsels, they bothered her for a few hours, but she went and hid for the rest of the day/night.  Monday afternoon I noticed she had some discoloration or patchy scale like areas near and in front of her dorsal fin.   >>Sounds as though the damsels did what dem damsels do and scraped the Gramma up a bit. >She is eating, is out and about, doesn't seem to be bothered by the other fish anymore.  Besides the 3 Damsels, I have a Canary Wrasse, and Lawnmower Blenny, various crabs, snails, shrimp.  All reside in a 55 gal with filter, skimmer, 2 powerheads, 70 lbs of LR and 30 lbs of live sand/crushed coral. Water Quality is 76.5 degrees, 8.2 pH, No ammonia, no nitrite, about 30 ppm Nitrate, and 1.024 SG. >>That level of nitrate can, over a period of time, be detrimental to the fish.  I recommend a few large water changes (on the order of 50% or better), then continue as needed to maintain.  Also, macroalgal growth can be helpful, as can the addition of a Tridacnid, T. derasa are hardy, attractive, and don't require huge amounts of light (I grew mine under normal output fluoros matched for best spectrum). >I have included a couple of pictures. >>Yes, very good shots at that, too.   >Should I be concerned with this?    >>Not overtly, but do have a hospital system and some antibiotic (I recommend Spectrogram) on hand in case.  I suggest first that, if you don't already, you begin a regimen of Selcon to the fishes' diet.  Nutrition is key to recovery, not just good water quality. >What is it?    >>External injury, in my opinion. >Treatment suggestions? >>Let the fish be, feed well, do those water changes. >Thank you. John McKnight >>You're welcome, John.  Marina

Fish aggression Thanks for the help, greatly appreciated, one last question; There was a clownfish added after the cherub and it was bothered for a day, and everything is fine now, it also had a grudge against the Dottyback, but now it's getting along fine, could territory not be a factor in this case? << Well I'm not sure who the troublesome fish would be, but some clownfish are really tough mean fish, but I only see that with the very large adults.  So I wouldn't think so here. >> Would adding another fish( some sort of goby) make it the new victim instead of the Sixline? << Doubtful.  Hard to see anything going over to pick on a goby.  But then again it is hard to picture anything picking on a Sixline. >> Would adding a more aggressive fish change the behaviour of the cherub? << Certainly.  But maybe not for the better.  I don't think I would add another fish in hopes of curtailing the aggressive behavior.  I think I would let them settle it out and get use to the fact that they are stuck there together. >> Thanks.! <<  Blundell  >>

Rogue Stomatopod? My girlfriend has a 20g reef tank and she's been having a problem with disappearing fish.  She had a small ocellaris clownfish since she first started the tank about four or five months ago.  A couple of weeks ago he mysteriously vanished over night.  A month or so before she put in a Firefish, which vanished within the first couple of days.  Three days ago she put in a pink skunk clown, and this morning he was gone.  None of these fish have shown any signs of stress or poor health.  She's got zebra leg hermit crabs, snails, a Ricordea, glove polyps, a couple of feather dusters, and an abundance of copepods that visibly multiply in the tank, and a clown goby who's been in there for about two weeks, and a more recently added electric eye scallop.  The goby is looking lonely, and Jenny's getting really discouraged, and thinking she should give up on fish all together.  Water conditions are primo, no amm, no nitrite, 20 ppm nitrate, 1.025 SG, pH 8.3...every invert she has every put in there has thrived.  We've never observed any predatory crustaceans, but I don't know what else it could be.  She's got 30lbs of live rock so there's plenty of hiding spaces.  As far as traps go are there any superior models or brands?  Is there anything else that would cause fish to disappear entirely? ***Hey Scott, Assuming these fish are not jumping out (something fire fish are notorious for) then it very well could be a mantis shrimp. Try examining the tank a hour after lights out with a flashlight - sometimes this turns up the culprit. One thing you could try is a hyper saline dip. Remove the rocks and soak them (do not soak any corals) in a bucket with salt water mixed to 1.036. This should cause any mantis that's hiding in the rock to exit almost immediately. Leave the rocks in this solution for no more than two minutes, as the hyper saline conditions could cause unwanted dye off on the rocks. The other option is a trap, and I believe there's one specifically designed for stomatopods. Do a search for "mantis trap" on the web and you should find it in short order if that's the case. If you do find a mantis, you might want to consider setting him up in his own small tank. They are very intelligent, and make fascinating pets. Good luck! Jim***  

Unexpected Lethal Aggression (9/5/04) Hi, <Hello. Steve Allen with you tonight.> I've been an avid reader of your forums, and have read CMA quite a few times.......at least each time a have encountered a problem. Well this time this email has nothing to do with water parameters, xenia not growing etc, but it has to do with a melee between my current fish 3 fish (maroon clown, six-line wrasse, and bicolor blenny) and a new addition to the tank, a yellow tailed damsel. I wanted to get something blue for my tank, so I thought the damsel was just the job. I have a 34 gallon tank, filled about 40% full of a mixture of liverock, and dry coral rock, which has been overgrown by coralline. So.....there are many hiding places. Quick water stats are: pH 8.2 Alk 11 dKH Salinity  1.023 Nitrate less than 5 mg/L Calcium 360 mg/L temp 24 degrees Celsius Lights are on for 12 hours a day and consist of 60 watts high int fluor's. So, as I've said I have the three fish, maroon clown, six-line wrasse, and bicolor blenny and they are all about 2 inches big. The clown is a bit bigger. <Yes, and it will get much bigger (5-6")and much more aggressive over time. You may regret choosing this particular clown for such a small tank.> They all have their favorite spots to hang out. So I brought home the damsel, he "was" about 1 inch, and acclimated him as usual and left the lights off about 1 hour, with only the hallway lights on. After about an hour, I turned on 1 lamp in the tank, and as soon as the six-line saw the damsel, hell broke loose!! <Sixlines sometimes get belligerent.> He would charge at him, even from the other side of the tank. Within about 30 min the damsel was really limp. Soon the clown and even the blenny had a go, and sadly about 4 hours after introduction it was all over......just a limp battered blue corpse. I even rearranged the rock work to upset previous territories, but that did not work either. <Did you do this before adding the Damsel or after the aggression started.> I have read that seeing that damsels can be aggressive, they are best introduced last, so I followed the advice, and look what happened. <Yellow-tails are less aggressive than most Damsels, and in this case you obviously had one that could not stick up for itself against your unusually aggressive wrasse. I'm surprised it did not find a nice little nook to hide in for a while.> This has been my first fish death in three years, I'm devastated. <Always sad indeed.> I know one had to keep an eye on the clown, but he was not such a problem. The wrasse was the biggest culprit. But that also the blenny attacked the damsel was a wonder. He would wait until the damsel was close to his hole, then charge at him and bite his tail. <Sounds to me like he was just defending his "personal space" as many fish are wont to do. Many erstwhile peaceful fish will turn highly aggressive if another fish approaches their chosen spot.> What did I do wrong, I followed all advice, lights out, changing rocks etc, but now I have a dead fish. <Regrettably, fish do not read aquarium books or follow advice. Everything written about fish behavior amounts to mere generalization that does not always apply to specific individuals.> I'm not new to fish keeping, but this really is something new. I can't see the tank being to small for 4 fishes, or what do you think. <It was apparently too small for the 4 individuals you ended up with.> Please help, I'm scared that if I introduce ANYTHING new that the same will happen. Would they attack a fish the same size, perhaps even a bit bigger, like a coral beauty, or 2 inch yellow tang? <Do not add a Tang to this small tank. It needs at least 75G to grow and thrive. A Coral Beauty or a Cherub Angel might be good choices of blue fish, but they can be nasty themselves. As I mentioned, the Maroon Clown may eventually take out all others in this size of tank. If you want to add another fish, I'd suggest an major rearrangement to be truly disorienting. You may even want to add a bit more rock. Be sure that there are lots of hiding places. Trouble is, you may have a particularly intolerant Six-line that will attack any newcomer. If so, you might want to consider replacing it.> Kind Regards, Chris B <Good luck, hope this helps.>

Tang aggression toward clownfish 8/16/04 I have a 3 1/2 inch purple tang and I added a 4 inch Yellowstripe Maroon Clownfish last night. The Tang is tearing up my Clown. The clown is just sitting there and taking it to the point that there are tears in the Clown's fins. Will this fighting stop? The only refuge the clown finds is in the Rose Bubble Anemone that I have but when it closed up, the tank attacks.....is there any suggestions that you might have to get this to stop?  thanks, JB <JB, Sorry for the slow reply!  Fist of all, I am amazed that the clown is taking it.  Generally maroons are very aggressive and don't take any abuse from anyone.  Unfortunately tangs are quite aggressive as well.  If this has not stopped by now, one or the other will have to go as soon as possible.  You don't mention much about tank size or hiding places.  75 gallons is a reasonable minimum for either of these fish at their current size, but may not be spacious enough for them to cohabitate.  The problem will be worse if there are not a lot of nooks and crannies to claim as territory.  Best Regards.  AdamC.>

Tang aggression toward Clownfish 8/16/04 There is a lot of hiding places for them both. I took the tank out and put him in m QT tank for a day and a half and let the clown settle in. The tang has stopped most of the hard attacks. He darts at him but that is about as far as it seems to go now. He is not tail swiping him anymore. The clown is defending his space a little better now and things have really calmed down compared to the other day. The tang is actually letting the clown swim around the tank some now, thank God. Thanks for the help. JB <Good to hear!<

Fish aggression? Hi friends, <Hello there> I have a 90 g. sw tank with a valentini puffer "Nurmal", flame angel "Hot lips" and neon goby "Goby1Kenobi". <Good names> The puffer had ich the first week I got him, I hadn't quarantined him so I removed him from the main tank and treated him with formalin and hyposalinity for a month). After a month of QT ich free, I reintroduced the "Nurmal" back in the display tank. I'm really worried about him. He's still eating well but breathing very heavily all day; even when he's sleeping...He paces back and forth along the tank, although that behavior is subsiding somewhat. <If he/it's eating all will likely be well> These are the same signs he showed before the ich appeared. It's probably related to a big puff up he had at the beginning of the week. Should I put him back in QT just in case, or wait until the telltale ich spots appear? <I'd hold off for now> Alas, another disappointment today. My flame angel has really taken to the puffer, and follows him everywhere. The flame is usually scared of her own shadow, so I find this social behavior odd for her (she chases the neon goby off constantly when he follows her!) The puffer doesn't seem annoyed with this tagging along in the least, but I noticed a crescent shape bite on the flame's dorsal fin! After the bite occurred, the flame is not fazed or stressed at all; quite the opposite, she seems to be dangerously close to the puffer all the time! She brushes her tail against him, sometimes on purpose(?) and I even saw her gently pick at his side (maybe removing parasites?)-the puffer was very still. <Keeping ones "enemies" close is often a good strategy> I'm not sure if she's asserting her territory-it doesn't seem like it. She seems friendly and not aggressive, and he for the most part ignores her. It's a huge tank for such small fish and yet she keeps hanging around him! I don't know if I should return the puffer to the LFS. I really love the little guy but don't want to risk injuring the flame:(((( <I'd wait on the Flame Angel/Puffer liaison as well. Perhaps a nice long walk, some fresh air will calm you. Bob Fenner>

Night Raider? (Mantis Shrimp- Or..?) Crew- <Scott F. your Crew member tonight> Thank you for your continued wisdom.  Two quick questions: 1) Over the course of the last 2 months, we have had 2 small (less than 1 inch) clown gobies mysteriously disappear in our tank.  Likely culprits are a Sally Lightfoot crab and/or Emerald Crab, but wonder about the possibility of a Mantis Shrimp in the tank.  We have heard some clicking at night (very little), but other than that and the disappearing fish, no other signs.  The 45 gallon reef tank also has a coral beauty, cleaner shrimp,  BTA, and several species of live coral.  We have not lost any other fish, or any of our hermit crabs/snails that also inhabit the tank.  Any thoughts? <I'd implicate the Sally Lightfoot, myself. However, there is certainly a possibility of a Mantis Shrimp. You may have to try baiting it out with some meaty foods...> We'll take a flash light out tonight and observe post lights out behavior. <Great idea> Could the Coral Beauty be at risk if we do indeed have a Mantis or Pistol Shrimp? <Yes, there is that possibility, but I wouldn't panic yet. Do perform your nocturnal observation, consider baiting the animal (if it exists), and waiting patiently> 2) We had been having problems hand feeding our BTA, now clown less after our highly aggressive tomato clown had to be removed after beating up our Coral Beauty.  Just this week he began to fully take in the food and digest it.  However, much to our dismay, the cleaner shrimp has decided that the BTA is a good feeding ground for him.  Last night we observed the cleaner shrimp pull the food out of the BTA's closed mouth.   <An annoying habit> He literally stock his paws into the closed mouth and yanked it out  (quite violently) - this occurred about 2 hours post-feeding.  One thought is that the cleaner shrimp is about to molt, and thus over-eating for the upcoming event. <An interesting theory> We are concerned about the BTA's well-being without a protector in a hosting clown.  Any suggestions for how to feed the BTA and keep the shrimp fed/happy at the same time? <If it were me, I'd feed a bit more food than the shrimp could grab at one time. Be prepared, of course, to remove any excess that the anemone doesn't ingest.> I know these sound like basic questions, but didn't see any apropos responses in the FAQs.  Hopefully you can be of some assistance. Christine <Well, Christine- these are very good questions. Unfortunately, like most aquaristic endeavours, there is no one perfect solution to either of them. I would use my suggestions and your excellent insight as a starting point, and use a healthy dose of patience as well! Good luck! Regards, Scott F.>

Hippo Tang And Royal Gramma (6/11/04) Hello WWM Crew.  <Hi there, you have Leslie here. > I would like to say I love your website. I just discovered it not too long ago now I use it every day.  < That's great to hear and thank you.> I just bought a small hippo tang for my 55 gallon tank. He is about 2 inches. He is housed with a blue mandarin, dwarf Hawkfish, yellow fin fairy wrasse, Chiseltooth wrasse, 2 percula clowns, royal Gramma, small yellow tang, lawnmower blenny, and a coral banded shrimp. <YIKES>  I know I shouldn't have some of the fish I do in a 55 but I am upgrading to a 180 this summer.  My problem is ever since I got the hippo tang my royal Gramma has been going after him. He has not bit any of his tail off <Well that's good>  but he seems to charge at him and attack him from the bottom. Is this a cause for concern? <  Yes I would say so.  I would be concerned. > What should I do?  <I would remove the one of the 2 fish.>  And I also have another question I am at the point where I am adding my last fish.  < My advice to you would be not to add any more fish in that tank, you are asking for trouble, it is to small for the fish you have in it already. > Wait until your 180 is up and running.>  And I have always planned to have a Fu Man Chu lionfish as my last. <It's best to add these as one of the first with the more aggressive species following and most aggressive  and territorial last.> But my question is will he eat my coral banded shrimp.  <It is possible.>I have asked many people about this and they all say as long as you keep the lion well fed he will show no interest in the shrimp. It is very dangerous to overfeed Lionfish. Please have a look at the article on Lionfish  http://www.wetwebmedia.com/lions&rels.htm And other people said that the coral banded shrimp is too big for the lionfish to eat. Is this true?  < Can't say for sure. It would depend on the size of each, if it will fit in it's mouth then it could eat it. Thank You Very Much, Louis <Your welcome, Leslie.>

A Werewolf in Tank? <Ah whooo! Warren Zevon> >Hi Folks,  >>Hello.  >Thanks so much for being here when we hobbyists need help. Can you help me out with a predator situation?  >>I can certainly try.  >I have lost a red headed fairy wrasse and 2 Fridmanis over the past 3 months and cannot figure out who is chowing on them. My water quality is perfect so I am positive that they did not die au natural. I also have never found a body.  >>Know that this is not unusual, even with jumpers.  >I suspect one of the following: a purple and pink lobster (1-2 inches long) a sally lightfoot crab, a Large yellow brittle star, or my aggressive coral banded shrimp. Can you please give me an opinion?  >>Wow, from that group? Any/all of them are very likely suspects! Sorry I can't help you narrow it down better, but I've got to be honest with you, and I would suspect all of them. Who knows, it may be a sort of "one of each" situation.  >Thanks a bunch, Matt  >>You're welcome. If it were my tank, I'd remove all possible culprits (that Sally lightfoot would be a real trick to catch without a trap). Marina

Disappearing Fish (1/20/04) Disappearing, thank you for being there for those of us who want to learn to navigate ourselves better in our aquaria. <A pleasure. I'm learning much here myself.> My question for you is in regards to two disappearing fish.  The first is a blue neon goby.  The first one I suspect died from starvation (LFS told me to starve the tank to decrease the diatom bloom).  I waited several months and got another to assist with disease control, even though we did not suspect a problem with ich or other parasites. The second was cleaning everybody (two ocellaris, one dwarf pygmy angel, one six line wrasse), though was harassed by the wrasse every once in a while.  Our clean up crew consists of assorted hermit crabs, snails, three serpent stars, and two brittle stars.  One of the brittle stars is rather large, black and with almost a tiger pattern.  Could he be the culprit. <Doubtful. The Green Brittlestar (Ophiarachna incrassata) has this reputation, not others.> We also have several soft corals (mushrooms, Cladiella, Pachyclavularia, pulsating xenia and a cabbage leather.) The tank is a sixty gallon hexagon with 70 pounds of live rock and a three inch sand bed.  Nitrates run ten or less, nitrites are zero as is ammonia.  Our long term fish have been with us for more than eight months and the tank is over a year old. <So many possibilities why this small fish disappeared. May have jumped. If it died in the tank, you cleaner crew could finish eating it in one night. Could have even harassed to death by the clowns or the wrasse when you weren't looking. etc.> The other fish that we seem to have trouble with is a royal gamma Basslet.  The first one was added with the clown as one of the first fish.  The two got into a fight and his injury lead to his demise. <Clowns can be killers.>  We bought another two months later as we adored him and he was dead within two weeks, the classic breathing heavy and lying near the bottom. <Many problems cause this symptom> At that time the LFS encouraged us to treat the tank with Kick Ich, which we did. <Bad idea & wasted $. If you saw no spot, treating for ich based on those symptoms is not needed because is more likely something else. Also, Kick-Ich does not work, and it is unwise to put any "medication" in your main tank. Too risky. Read more on WWM.> None of the other fish which we added since have had any problems except the neon goby.  Any insight would be very appreciated. <as above> Should we consider a red headed goby for disease control or stick with the neon goby?  <I'd go with a cleaner shrimp myself. Your best defense against disease entry is to quarantine all new additions for 30 days. Easy & cheap. Read on WWM.> Thank you so much, it is a pleasure to read you daily. <Hope this helps.>

Limiting Aggression <hello, Ryan with you today> I'm attempting to limit aggression by trying a little trick with my fish, so here's the plan; I have a Goldentail moray, and a miniata grouper both are juveniles. I know my Goldentail gets along with snowflake morays, because he was housed with a few when I bought him and I had him in with one for awhile till I sold him to a close friend. <OK> I recently miss having a cute little snowflake in the tank, so I plan on adding one back, but I know that by now my Goldentail will rip anything apart that's an eel. Even knowing that the one he was housed with before was much smaller then him, and he never showed a bit of aggression towards him. So here's my plan, I'm going to take my grouper and Goldentail, and put then in my sump (for up to 250 gallons, so its about the size of a 30 gallon tank) for 3 weeks to a month; Then mix all the sand up where it looks totally different (no holes left that either one of them made); Add a bunch of new pieces of rock work, and change the setting around, and add the new snowflake to the tank (after quarantine of course). <Not sure if I'm crazy about using the sump...I would quarantine for a month, skip the sump>  Therefore when they get added back the snowflake will be settled in, and hopefully they wont remember it as home after being away so long;  Also maybe after being in such a smaller area for awhile they wont feel a need to hold so much aggression towards the other tank mates in a much larger tank. <Likely never make it back> The common sense factor comes into play when making this plan, but as we all know marine fish, and especially moray eels have many surprises; So do you believe that this step of events will raise my chances of seeing my Goldentail sit next to a snowflake in harmony once again, or would I be wasting a lot of time here? <I think you're wasting time...The eel wouldn't stay in a sump for very long, you're probably going to find him dried up somewhere.  I think your best bet is to stay with one eel.  In the wild, eels give each other space.  Predators like this should be respected, and understocked for best results.  Good luck, Ryan>

Battling Fishes... Hi Scott, how are you doing, hope you're doing great in the holiday season. <So far, so good! Hope that yours is going well, too!> Well Scott, just writing to say hi, and to ask you a few questions. The last time I wrote you I told you about my home tank in which I have: 5" harlequin Tuskfish 2" Naso tang 1" passer angelfish 1/2" (now) Cortez angelfish. and the last addition was one of my favorite fish that I was trying to get for a very long time a 3" magnificent fox face fish (silver fox face). (stunning beauty). <Quite a mix! Lots of Color and action!> These baby's were in my home tank a 90 gal tank, now that there are baby's, in where intended to get them in to my larger office system (that was contaminated with the carburetor house 3 months ago), and then to the 300 gal system that I am planning to get next year. They were all living peacefully. <Excellent- glad that you're preparing to move them to larger quarters in the near future!> Until 2 days ago, the harlequin was harassing the Naso Tang and the Silver Foxface. The only thing I could do is take the Harlequin out and put him in my office system. <Often the only solution for an aggressive fish...> The problem was that the 2 survivors of my office catastrophe (5" Miniatus Grouper and 10" Zebra Eel) may harass the harlequin. <An unfortunate turn!> The minute the Harlequin entered the system the eel ignored him, but the grouper started fighting. Every single fish that ever enters that system has the grouper act very aggressive to it. The only one that put him in his place was a 4" Clown Trigger that died in the house incident. <Wow- I guess that he's at the top of the pecking order in this tank!> The only thing to do was to take out my beautiful grouper to the fish store, (I was in love with that fish but it was to aggressive). <It's a tough call. In the end- maybe not a bad move- as these fishes get very large...> I got some credit for my fish and brought home a beautiful Sailfin Tang (red sea), that are all getting along in my home tank. <Another great fish- but it does need some space- it can reach 15 inches plus!> But the grouper left the harlequin's tail damaged, like a broom and with peaces of the tail missing. <Keep a close eye on the tail is it heals. Keep water clean to make sure that there are no potential infections...> The fish is eating great, and lives very peacefully with my lacy eel, but will the tail regenerate??, <It should, with good water conditions and overall care> I all ready put some Marine Max in the tank to help heal the wounds, but will the tail ever be the same as it was?? <Hard to say...It certainly CAN be, but it may be a bit different than it was...> Please give me some advice in what other matters should I take to help him heal the wound. <As above- good water, good food, and no harassment!> Other good news is that all my other fish are doing great, and I took your advice, and put some live rock with algae attach to it (sea lettuce), and it was growing great, until the Foxface, and the Naso Tang started playing with it, it was there for them to eat it, but slowly, not completely destroying it, so, I took what the left, about 80% of the plant and bring it to my office tank to grow it, and then take home small amounts for them to eat. <Good idea- maybe you could try to culture some as a supplemental food for your tangs? Well worth the effort!> But what do you recommend for my plant to grow quickly, I all ready add some Zo?vitamins and HUFA vitamins, but does it need to be near a window so the sun hit in directly?? or just the 50/50 bulb lights?? <Well, Zoe and HUFA are supplements for fishes, and will not do all that much for the algae. I'd recommend a dedicated culture container, moderate to bright light, water from your display tank, and supplement with some iron...This is a good recipe to get most macroalgae to grow> Is it true that some algae is illegal to purchase in the U.S., if is true , please name 1 brown, 1 green, and 1 red, hardy, good looking, and not illegal algae I can purchase in the U.S. Thanks again.. <It is supposedly illegal in California to sell certain forms of Caulerpa, but I am not aware of any other forms which are banned. I'd recommend that you try Gracilaria- a great red macroalgae that tangs love.> Thank you some much, for your time and advice, your help has been great for my and my fishes. Att. Juan Santos. <Glad to hear that, Juan! Keep up the good work! Do try growing the algae- it's kind of fun, and your tangs will love you for it! Regards, Scott F>

Cleaning crew aggression and not so mysterious deaths - 10/10/03 Hi guys, my question is regarding the compatibility of some of my invertebrates. <Hi. Paul in today. Sorry for the delay>  The animals in question are 3 peppermint shrimp, 1 coral banded shrimp, 2 Brittlestars, 1 sally lightfoot crab, 20 blue legs hermits, 20 scarlet hermits, 3 emerald crabs, 1 porcelain crab, 1 orange Linckia starfish, and 20 turbo snails. <That is waaaaaayyyyyyyy too many inverts in such a small tank. My goodness!>  I have a 29 gallon tank <unbelievable......> and feed small amounts of brine shrimp and flake food 3 times a day. <Do you have fish as well?? That is a lot of food>  The problem is that it seems one of these guys is killing off the others one by one almost daily. <I am not surprised one bit. Firstly, Do you check water quality? Secondly, these animals are mostly if not all omnivorous. They are opportunists for sure. They will eat most anything. They usually come to you lean and mean so that they may "go to town" in your tank and prove their worth to you. There is no way this tank will support 2 brittle stars (forget the Linckia) the shrimp are in trouble (brittle stars have been linked to their disappearance at times) Crabs are fairly aggressive eaters and turn to other "things" when they feel they are not getting enough of what they like. Hermits will eat each other when in cramped quarters even with enough food, and there could not be enough algal matter to support all of those snails let alone all of the others who will rely on it for sustenance. Lastly, I wouldn't be surprised if you are having water chemistry issues. Feeding three times a day, plus the very large bio load all in a 29 gallon tank. Did these all come in at one time? (I will assume they did)> 3 days ago it was one of the emerald crabs, then the sally lightfoot, then a Brittlestar.  The Brittlestar had the most noticeable damage thus far. <Again, I am not surprised>  I awoke to find it missing two legs and having lacerations across it's central disk from where one of the legs was attached.<Again, I will assume that these came in a package deal. Which may mean that you acclimated them and added them all at once within 24 hours or so. How long after their addition did you notice the issues being described above??>  Once I got back from lunch it was even more injured than before.  I haven't seen the porcelain crab for a while either. <Could be a goner>  This has just started in the past couple of days <How long after they were introduced?> - who do you think is the culprit <I am leaning towards you, mate> and what can I do to stop my animals from getting killed? <Well.......................do research you inhabitants and their environmental needs before purchasing. Seek advice before change, then make the best decision. A lot can be found on various websites, books, and clubs. I am sorry for my lack of tact here, but sometimes and aquarist needs to be saved from oneself as well as the animals in his charge. I can't stress enough to read about your animals before purchase. There is usually some detail as to how many per gallon or per tank size listed and in some cases even info for compatibility. If there isn't, find a reference for it, or ask someone. My only advice on this manner is to maintain water quality, hand feed when possible, and either give away, sell (maybe), or move (to another tank) some of your dudes. Under normal circumstances these animals sometimes have some mortality in shipment stress (nothing you can do about it) but a lot of mortality comes from acclimation. We have much on our site (not only on a per animal basis but also an actual general acclimation site as well. Quarantine is another good idea. You might even already do this, I don't know. Read through our site a bit. There is hope for you and your animals. The ever winding path of learning! Let me know if there is anything more I can do -Paul>  Thanks, James

Rumble On The Reef! Aggression First, thanks for your help.  Your website has helped me many times and it seems that many others feel the same way. <That's great to hear! I'm privileged to work with some outstanding people on this site (who just happen to be uncommonly talented aquarists, too! Scott F. on the keyboard tonight!> I have a 125 with a fairy wrasse (3"), 6-lined wrasse (1 1/2"), 2 clowns (1 1/2") 1 cardinal (3") a fusi goby, circus goby,  bi-color blenny, 7 chromes (less than 1") and 1 yellow tang (4"), 2 cleaner shrimp.  Lots of swimming space, a number of corals and water quality is good. <Yep- sounds like a nice mix of small, colorful, and interesting fishes! I like it!> The yellow tang and chromes were recent additions.  Prior to them, I had 1 Pacific Sailfin and 1 Short-Nose Unicorn (purchased before I started doing research on fish size!) They started looking small in the tank so I donated them to the local Aquarium (they will be in multi-thousand gallon tanks, which is where fish that size belong). <Wow! That's cool that the local aquarium took them...This is a pretty rare occurrence, and a very lucky one for those fish! I can't think of a better captive home for some potentially large tangs!> When I added the new fish (chromes and tang), the tank aggression suddenly shot through the roof.  The fairy wrasse is now aggressive towards everything (I guess the Sailfin and unicorn kept him in check). The tang chases pretty much everyone around and EVERYONE picks on the Chromis. Is this something I should worry about and at what point is aggression too much? <Well, you should always be concerned when aggression rears its head in your tank. However, I think that there is a certain amount of "shuffling" going on in the social order, and fishes that were not in a higher position in the hierarchy are asserting themselves...A common, and expected occurrence in a system where the "alpha" fish(es) have been removed. As they say, nature abhors a vacuum, and somebody has to rise to "fill the void", so to speak!> Next question is what to do about it?  Remove the aggressors and will something else take it's place?  Remove the victims and will there be new ones or just let the fish sort it out? <Well, unless you're seeing some definite "by products" of the aggression, such as fishes not eating, displaying obvious damage, and hiding, I'd see if things settle down without your intervention. If the situation deteriorates into a real problem, I'd consider removing the guy that's doing the dirty work...Alternatively, you could try re-arranging the aquascaping, to "break up" the territories, which may help "level the playing field" or a while...> There has been high change in the tank which may be contributing temporarily to tank stress.  I am increasing the size of my substrate at around 1" a week to create a DSB (currently have a nutrient sink) and recently increased the water flow, both of these after reading articles on your website. <Both are good moves...Both will create a bit of confusion for the fishes at first, but they should adjust to these new parameters in short order> Lastly, I would suggest a part of your website dedicated to fish aggression. Seems to be a big factor in raising saltwater fish. <Not a bad idea...Yes- aggression and territoriality are common concerns with marine fishes and inverts (and, by extension, corals, which can wage "chemical warfare" as part of their aggressive repertoire)...> Thanks for your time. <And thanks for stopping by! Regards, Scott F>

Rumble On The Reef (Round 2) Here is an interesting follow up.  I used to only feed a wide range of frozen food (mysis shrimp, enriched brine, plankton, squid, etc.). To reduce nitrates down, I experimented with dried food because I have read that is has less nitrates.  For the last couple of weeks it was only dried food (twice a day).  A couple days ago, I switched backed to frozen food (twice a day) and the aggression has noticeably dropped.  What happened? <Wow...ya got me on that one...Maybe, the fishes preferred the frozen foods, and after a week of flakes, they became more interested in the frozen food than they were in beating the crap out of each other!? Or, it could simply be a coincidence...The longer that these fishes were together, the more "used to each other" they became...Either way, lets be thankful! Glad to hear it! Regards, Scott F.>

Aggressive Moray Eel >Hi, >>Hello, Mike. >I think my snowflake moray is eating all of its smaller tank mates.  I have a 85 Gal Acrylic aquarium with  a lot of rock for hiding.  The fish inhabitants are a 4" yellow tang, 6" red emperor snapper and a 20" snowflake moray eel.  The fish that have disappeared in the last two weeks are a 3 lined damsel, 2 tomato clowns and just recently a 3 1/2 " Niger trigger.  I suspect the moray for several reasons, one the fish are accounted for the previous day  then gone the next morning.  Also I saw the moray foraging through the crevices in the rocks finding the trigger sleeping and harassing him.  A couple of days later the trigger had a bite mark on the top of him.  Now he is just gone, no trace of the trigger at all.  By the way these fish (excluding the clowns) have all been coexisting somewhat peacefully for about the last 4 months. About three weeks ago I moved the two tomato clowns from my other tank into this one, they disappeared in about two days then the damsel disappeared then the trigger. I don't think it is the snapper, as long as he is fed he pretty much leaves everyone alone. I have been feeding them more goldfish lately, that is the only change in the last 6 mo. Any info would be greatly appreciated.  Mike >>Yes, Mike, it's definitely the moray.  He should be removed ASAP, they are known for this kind of behavior, and are tricky to have co-habiting with other fish (*especially* fishes of the tasty sizes you've described).  Also, please, do NOT feed any marine fishes goldfish.  Generally, goldfish are just terrible as feeders for any fish, but it's especially true of marines--this has to do in large part with the fats found within a Goldie's tissues.  You would do much better (as would the fish) if you trained them to take marine foods such as squid, krill, clam, octopus, and shrimp from a feeding stick (unless they'll take it floating).  Good luck catching the Snowflake, and I'll advise you to be very careful when netting and placing into bag or bucket, they can move VERY quickly, and I've been doinked twice by them.  If you are bitten, do NOT pull away, as this will just make the wound worse, he *will* let go, pretty much immediately.  Marina

Learning From Tragedy Today is a sad day. Neb, our snowflake eel turned stark white, and it looked as though the other fish were starting to bite him. <Sorry to hear that!> We've had Neb for about 8 months, he was a juvenile that doubled in size during the time we had him in our 90-gallon tank. Our other fish (1 clown, 1 niger trigger, 1 dog-faced puffer) seem fine. We noticed that the niger trigger was starting to go into Neb's plastic tube that's buried in the sand. Could the trigger have stressed Neb out? <Quite possible. Despite the predatory reputation of Snowflake Eels, they are generally somewhat shy and reclusive in their habits, and will simply not compete with more aggressive fishes like triggers and puffers> We are also wondering if the diet was okay, we were feeding Neb shrimp soaked in vitamins on a skewer. <Well, that's not a bad component of his diet. However, all animals should receive a varied diet, consisting of other foods, like krill, chopped squid, clams, etc...Variety is important. Good though on the vitamin supplementation, though> Really sad to lose that beautiful creature. Any insight you might have would be appreciated. Thank you, Connie <Hang in there, Connie. I'm sorry to hear about your loss, but I know that you've learned something, so that's why this tragedy will not have been in vain. Don't let it dissuade you from growing and learning in the hobby. Good luck! Regards, Scott F>

Who Dunnit? Mystery marine aggression Hi there,    I have a question about aggression.  I have a tank with the following animals: Falco Hawkfish (Cirrhitichthys falco) Fuzzy Dwarf Lionfish (Dendrochirus brachypterus) Red Soldierfish (Myripristis violacea) Blue tuxedo urchin (Mespilia globulus) Arrow crab (Stenorhynchus seticornis) (fairly large--about 5-6" across the legs) Red starfish (Protoreastor linckii) Sand sifting starfish (Astropecten polyacanthus) I had a Potter's Angelfish (Centropyge potteri) who I thought would be ok in the mix.  However he was battered a quite a bit and before I could get him out of the tank he died.  I replaced him with an Australian Dottyback (Ogilbyina novaehollandiae) and a Blue Devil Damselfish (Chrysiptera cyanea) who I thought would be better able to compete with the rest.  That has proven to not be the case as the Dottyback became quite battered and I had to separate him.  The other fish don't seem to be having any trouble except:  the Soldierfish has a split tail fin that has been healing for a while.    My question is this:  Who do you think the culprit is?  The Hawkfish was the second to be added to the tank (after the lionfish) and I thought he might be the culprit but I am now wondering if the arrow crab might be the one doing it.  Is there precedent for this?  Why aren't the other fish affected?  I guess I'd just like to know who's responsible. Thanks for all the help. Erik Jorvig < The culprit is probably either the hawk or the arrow crab.  You should always add the more docile fish first then add the more aggressive ones.  The other fish aren't affected because they have an already established pecking order.  When you add new fish try rearranging the rockwork or somehow disrupt their territory.  Also when you add new fish turn off the light until the next morning and feed the tank before they are introduced.  The potters angel is also a very delicate fish and needs to be housed with more docile tank mates.  Cody>

Shredded Emperor Hi guys, haven't had to talk to you for a while <Drop by more often! Scott F. here today!> My Imperator has one fin that appears to be ragged and fraying and am starting to believe that it is one of it's co-inhabitants (trigger or snow flake that may be causing this. <Well, it certainly may be one of the other inhabitants, but it may also be caused by random contact with rock or coral, or even environmental factors> Any suggestions on how I can correct ? <Well, unfortunately, if it is caused by another fish "picking" on the Emperor, you're probably going to have to separate or remove the offending party! As a "supplemental" suggestion, keep an eye on the fish to make sure that the fins do not become infected. Keep the water quality high and the feedings plentiful and of good quality> These animals are currently housed in a 110 gallon sparsely furnished tank...Maybe if I add some rock/hiding places might do the trick. <That would certainly be a good idea if you suspect that someone is getting "frisky" in there. I'd try that before removing one of the animals. By creating more defined "territories" within the tank, you may be able to reduce the possibility of this happening on a continuous basis> Let me know what you think Thanks. Chris <I think that you have the right idea, Chris! Good luck! Regards, Scott F>

Re: Yellow Tang Illness? My wife and I are new to Salt Water Aquariums.  We have been doing everything told to get the best water results.  Over this time table we have introduced new fish as allowed with instruction.  Yesterday we introduced a Powder Blue Tang to our 55 Gallon Tank.  Now we notice that our Yellow Tang has become very pale in color and has almost a dandruff look to his body.  We also introduced a cleaner shrimp (2).  Please advise if the Yellow Tang has become ill.  He acts more shy and has focused toward one corner of the tank. <Mmm, sorry to state, the new Tang is not an aquarium-hardy species, and placing it with a Yellow Tang not a good idea (they're not very compatible)... Likely a latent parasite (ich and/or velvet) has been "triggered"... Much to say re these issues. I strongly suggest going to our root web: http://www.wetwebmedia.com/ and using either the Marine articles index or the search tool there to study about Tang compatibility, Tang Disease, Cryptocaryon, Amyloodinium/Velvet... Quarantine... and quickly. Your fish/es will soon be dead w/o fast action. Bob Fenner> Thank You Dana Ramos

Separating aggressive fish/es Another update. . . the fish are still awaiting their new tank -- however I think the small tank is getting to my wrasse and maroon clown. They have been going at it and maroon clown took a beating yesterday.  I put her in a Tupperware container (with plenty of holes) in the tank pretty close to the return so she can get some water flow.  How long would you suggest leaving her in here? The tank won't be here for another two weeks and I hate the thought of having her in there for that amount of time.  Please give me your suggestions. . . thanks! :) <I would use a floating all-plastic colander instead (most do float) and leave them separated for the duration. Not likely a problem. Bob Fenner>

Re: Clown Trigger Down in the Dumps Thanks for your response. . . here's my problem though. . . . my sick tank crashed a week ago and I don't have it up and running again yet.  I would have to put my trigger in a separate container (Tupperware with holes in it) within the larger 160 gallon tank.  Is this ok?  I know it won't give Trigger the space he's used to but will this suffice for the time being?   <Yes, as a matter of fact, an all-plastic colander floating with some air trapped under the edge works great. Bob Fenner>

Re: new fish problem (Grouper bugging New Angel) HI, <Greetings!> I just added a small (3") queen angel to my 90g tank.  The problem I'm having is with the Blueline grouper (4-5") that's been in there about 2 months now.  He's been harassing the angel by darting at him, keeping him pinned up near the front surface part of the tank.   <Keep watching this behavior. It's probably not going to get better but worse! These guys do tend to be aggressive> He doesn't strike him, just pestering him.  The angel seems ok, he just flinches a little and otherwise doesn't seem too bothered except for being sort of corralled.  Do you think the angel will have to be removed, or can he put up with this and get used to the grouper's behavior? <Keep watching...If the behavior doesn't lessen and then stop in a week or so...the tank ain't big enough for the both of them!> Will the grouper's aggression subside?   <Time will tell> I'd like to know your thoughts before trying to take him back to the LFS.  Thanks for your help. Tim <The Queen will grow up to almost 18" and will eventually become very aggressive. Quite frankly, your aquarium is too small for the long term keeping of this fish! Check out wetwebmedia.com for more details on the keeping of this and many other fish. David Dowless>  

Deteriorating Fins? Hi Dr. Fenner, <Anthony Calfo in your service> I was looking through a pet supply magazine and noticed a product that is supposed to remove electricity from an aquarium. It was only a grounding wire connected to a titanium rod on one end and the other to the grounding screw at the outlet. I had been mildly shocked on several occasions while in my aquarium so I constructed my own grounding wire using a stainless steel rod. So far it has worked. <excellent> My question is, the magazine stated that electricity in the water can cause deteriorating fins. I just removed a fish from my tank because I strongly suspected him of chewing on my 3 Searobins. I have not observed any aggression from any of the other fish, yet the Searobin's fins seem to be getting worse. My water quality tests out excellent. I have been treating the tank with copper at around .25ppm. Do you think the voltage in my water could have caused the problem with the fins, or is it something else? Thank you, Steve Tilotta <stray voltage has been implicated as a deleterious influence on the health of fishes but cannot fairly be said to cause anything so specific. Enough said that it is a stress and can contribute. I think that it is generally wise to have stray voltage grounded but would not rule out the possibility of a pathogen or aggression with your sea robins. Anthony Calfo

Deteriorating Fins? II Thank you Anthony for your advice. <always welcome> An update: I caught the culprits that were chewing on the fins of my Searobins. They were my spadefish.  <hehe... yes, Cheeky little monkeys!> Butterfly fish seem to leave the Searobins alone. I think I'll fill my tank(135 gal.) with an assortment of them if they don't fight amongst themselves. Thank you again. Steve <eh... you'll get a whole new set of challenges/problems <wink>. Anthony>

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