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FAQs about the genus Chromis Damsels 1

Related Articles: Chromis Damsels

Related FAQs:  Chromis 2, Chromis Identification, Chromis Behavior, Chromis Compatibility, Chromis Selection, Chromis Systems, Chromis Feeding, Chromis Disease, Chromis Reproduction, Damsel Identification, Damsel Selection, Damsel Compatibility, Damsel Feeding, Damsel DiseaseDamsel Reproduction

A couple of nice Chromis viridis in Australian waters.

- Quarantine Issues - <Good morning, JasonC here...> I'm not sure what happened to this Green Chromis. He has been in the QT for two weeks and I noticed yesterday that he was swimming slightly off kilter. The QT is 10 gal with a bio wheel filter. The water specs are: Temp 26C (in the past two days it has ranged from 28 to 25) Ammonia 0 Nitrite 0 Nitrate 0 Sp G 1.023 (was up to 1.027 a couple of days ago but I've been adding freshwater to bring it down) I do 20% water changes every other day with water from my main tank (same water specs but 27C). I thought he might have had HLLE because I could make out a black line from his head along his side to the tail. I noticed the line two days ago. He had not been eating as well as the other Chromis in the tank. The LFS told me that is such a small QT I should only feed them once every three days and only so much as they could eat in 3 minutes. <There is some truth to this - 10 gallons is a small system, and the salinity and temperature fluctuations will be more drastic in a tank of this size. Always be very careful to minimize the impact of such changes.> These are/were my first fish and I would sure like to keep this last one alive. <At this point it's probably safe to put the remaining fish in the main tank. The loss of this one Chromis was probably incidental, in other words not your fault, and now you know why quarantine can be useful.> I did notice that they looked a little blotchy but after I turned the canopy light on their colour came back so I figured it was nothing. This is the post mortem picture not sure if it helps. Jim <Sorry about your loss, but you are certainly on the right road... onward. Cheers, J -- >

Aggressive Chromis Hi Gang, <Hi Glen & Ang, PF here> I yesterday introduced 3 x Blue Chromis into an already established 90 Gallon tank whose current inhabitants are: 2 x Ocellaris Clowns 2 x Fire Gobies 2 x Rainford Gobies 1 x Blue Starfish Just now I closely inspected the inhabitants and found: 1 of the Chromis has a cut on the side of its body about half its width (rather deep) The starfish has a piece eaten out of one of its legs about one third the length of its leg The Firefish' tales are rather tattered. <Hmmm... this all seems strangely familiar...> I straight away put this down to the Chromis' defining who's boss in the tank. <Well, actually, Chromis are pretty mild mannered. My clowns don't put up with them getting near their hammer coral, or me getting near the hammer for that matter.> Should I be looking at removing these fish (my first reaction was to euthanize them, they are very very lucky my beloved clownfish are whole and healthy)? <I'd keep a close watch on the tank and see who the real culprit is.>  Is the starfish likely to live with such a wound (the wound is deep enough that I can see the holes of tentacles from the top of the starfish) and what precautionary measures should I take to ensure its survival. <Make sure it gets it food, and keep the tank conditions pristine. Things should be ok, they have amazing regenerative abilities.>  Have I made a blunder purchasing something remotely like a Damsel which I was advised from internet sources to steer clear of. <Chromis are, as has been said before, pretty mild mannered. Blue/devil/yellow/whatever damsels, OTOH, are nasty buggers.>  Any help you can give would be greatly appreciated, up until now marine fish keeping has been a very enjoyable experience. <They're just trying to make sure you get some excitement, ; ) > Regards Glen & Ang Melbourne, Australia <HTH, PF>

Sick green Chromis? Dear WWM crew, <You got Cody today.> I have a 29 gal. reef tank with (in order of their acquisition) 3 green Chromis, 1 orchid Dottyback, 1 bar goby and 1 coral beauty angel. Since adding the Coral Beauty, one of my green Chromis hangs out in the top corner of the tank, has lost coloration and does not seem "happy". His fellow Chromis come over to him and seem to try to nudge him into swimming with them, which he does occasionally, but mostly he just hangs out in the top corner of the tank. The fish are all healthy and my water has been tested by the pet store. The fish does not appear to have any signs of illness, but is obviously not feeling well. Can anyone help with what I should do? Should I take him out of the tank or get something to shield him from the rest of the fish? He seems to be ok physically... he eats a bit, looks a little thin to me... his fins are intact, although one is slightly ragged. I wonder if he is stressed from the new (Coral Beauty) fish, who is much more aggressive than any of my other fish, chasing the others about, but I do not know what to do for the poor little guy. Thanks, Diane <  This tank is too small for the coral beauty and he will need to be removed.  After the coral beauty is removed the Chromis should recover with good feeding and water conditions.  This tank is already pretty well stocked as it is.  Cody>

Rebel Chromis without a clue Gentlemen... >>And women, thank you!  Marina here. Over the weekend I added my first fish into my new 55gal... 4 Blue Green Chromis.  Once in the tank, 1 immediately bolted for a cave, and now 3 days later, he still hasn't come out.  I noticed his head peeking out yesterday morning, and then again last night, but as soon as I got closer he darted back underneath.  Since then there has been no trace of him.  None of them seemed to be sick or anything, and the other 3 are doing great.  >>This is not entirely uncommon. I was told by some friends that it is best to keep the Chromis in odd-numbered groups, but nothing to insinuate that it won't work out with an even number...  >>I know of no hard or fast "rules" concerning odd vs. even number in regards to damsels.  The issue is providing them with enough "buddies" that they don't become further stressed.  Other than that, it's more of an aesthetic issue. I haven't completely given up hope that he will come out, but I'm getting close.  The cave is under a good chunk of live rock that is in the bottom and center of my rockscape, so I definitely don't want to pull everything up... However, I am a little bit concerned that if he never loosens up, I will have a dead fish under there that's not going to come out easy.   Is there anything I can do that may help coax him out?  Should I just keep goin as is and hope for the best?  And if worse comes to worse, how badly will it affect my tank if he kicks the bucket under there? >>I know it's no fun to buy a fish to then never see it again, but he's peeking out.  If he's not feeding, or appears to be injured or otherwise stressed that would be a worry, but you've given no indication that either situation exists.  This particular fish is just not as "self-confident" as the others, and he should soon become hungry enough to want to feed with the others.  Are they feeding well, and are you testing regularly during this cycle period?  One small damsel will cause a bit of a spike in ammonia and nitrites, but a water change or two (or cranking up the skimmer) will suffice.  I don't think that will happen assuming everything else is good.  I think he just needs time to acclimate to his new living situation is all. Thanks in advance for any advice and/or suggestions.  Curtis! >>You're quite welcome, I hope this helps. Marina

Re: Rebel Chromis without a clue Marina Thanks... unfortunately, the lil guy turned up dead the day after. It looked as tho he had a cut on one side. I never saw anything on him before he went into the tank, so I'm not sure how it happened... possibly scraped himself under the rocks. I'm only guessing, tho. Thankfully, the remaining 3 are doing great. </P> >>Sorry to hear he was indeed injured, but I'm also glad that all the others are doing well. I've been checking the water quality daily all week, and nothing has gone seriously out of whack. I'm going to do a partial water change over the weekend, just the same, tho. I more or less had planned on doing that, anyway. >>Good plan. Thanks for your response and advice. Your website has really been a great resource for me. The wireless laptop, and comfy chair in front of my tank has pretty much all but ended my TV watching habits. Well... at least until y'all get a show on Animal Planet or something.... Thanks again! Curtis!  >>Very glad to have been of help. Marina

Sick Chromis I have a green Chromis that is having some trouble swimming/breathing. As per Scott F.'s advise I have moved him to a qt tank.  I now have some additional questions.  First of all since he is having trouble swimming should I leave the powerhead off to give him a break? or would the reduced flow rate be worse? <I'd keep the powerhead on, maybe at reduced flow, to keep some circulation going in this tank. In fact, if the powerhead offers an aeration feature, I'd utilize it.> He hasn't developed any white spots, but I wanted to do something.  I went to the LFS, and got a pH so that I could match the pH for a freshwater + Methylene blue dip (I also bought the Methylene blue), but upon returning home I realized that I had bought another saltwater pH kit and therefore had no way to test the freshwater's pH. I felt stupid, but wanted to do something so I did a saltwater + Methylene blue dip. I know this won't be as effective as freshwater + Methylene blue, but it's better than nothing, right? <Sure- the antibacterial properties of Methylene blue will still work in saltwater.> After the dip (which went well at 15 min.s with no signs of stress, for him or me; not bad for my first dip) I could see tiny particles laying on the bottom of the bucket.  Could these possibly be the parasites that have infested my little buddy? Or would they be too small to see with the naked eye? <Well, hard to say...If it is Cryptocaryon, it's unlikely that you'd see the actual parasites...but you never know. The material could have been body slime or mucus, or some type of precipitate. But you never know!> Oh, also the LFS was out of copper and doesn't sell copper tests, I was informed by the owner that he doesn't believe in testing (too bad he's the only one reasonably close to me) <YIKES!! With "friends" like this...yuck...> So, I am looking online, could you recommend a good test kit brand? Also are there better brands of copper? Or is copper just copper? <I like Cupramine by Sea Chem, and CopperSafe by Mardel. Both are good quality, IMO. As far as a test kit for copper, most of the ones that I have seen on the market are pretty good, IMO. Now- I like copper, but I wouldn't rush to use it unless you are certain that you're dealing with a parasitic infection. Some fishes do not do well with copper, such as pygmy angelfishes. Anyways- with your fish- be sure to keep up good water quality during his quarantine, supply high quality food, and observe closely. With time, and a little TLC, this guy can make it! Good luck! Regards, Scott F>> Thank you for your time -Luke

Re: sick Chromis thanks once again for your help.  i had 3 green Chromis in my qt, and all was fine for over a week.  then one day i noticed one wasn't schooling or eating and breathing rapidly in the corner.  then next day it was dead. <Sounds like Amyloodinium. AKA velvet> the other 2 were ok for a day more.  then the same thing happened to another one.  now its been 3 days since the 2nd died and the last one seems to be fine.  eating a lot and swimming fine.  no white dots or fuzzy stuff <Definitely velvet> and no visible isopods, the fish looked perfectly normal,  just rapid breathing and sitting in the corner.  i dissected the 2nd one and didn't see anything that looked like a parasite (with my crappy magnifying glass). any idea what this is?   <Definitely and obviously (from your description), velvet> could it have been something they had or did my qt tank have something?  i have a bi-color blenny that lives there full time and he seems fine through the whole event. <He's a really tough critter> or could they have had something all along that just got the best of them after a few weeks.  they were eating and very social for the 1st week.  my water parameters in qt check out fine too.  if you do have an idea what it is, can you recommend a dip / medication?  my thoughts were flukes, but since the 3rd seems ok, i didn't know how contagious they were? thanks again, Neil <This is just as contagious as ich. Please sterilize your tank before adding more fish. Check our disease files at Wetwebmedia.com There is detailed information about treating this and other diseases. David Dowless> <P.S. I'm a former North Carolinian from Fayetteville! UNCP graduate!> Neil A. Jacobs Department of Marine, Earth and Atmospheric Sciences North Carolina State University

Chromis schooling question Hello again crew, thanks for being there for us! <Our pleasure!> I am planning on purchasing about 5 green Chromis for my 135 gallon FO tank, in hopes that they will form a small school.  When looking at vendors online, I notice there is also another Chromis, the Half and Half Chromis, that is the same size, just a bright orange color. Two questions:   1) Will the green Chromis school readily? <We can never say definitely with any fish but your chances are very, very good> If not, could you recommend another small, peaceful fish? <Chromis are good> 2) If I were to mix the two species, would they school together?  I'm guessing not, but it might be interesting to get varying color in the group. <My instinct says "No" but I won't commit on this question. I'm just not sure. Fish have been known to act in ways not characteristic in the ocean. Look in several stores and see if you can find different schooling combinations. David Dowless> Jim

- Chromis Behavior - Hi everyone & Bob: <Hello, JasonC here...> Just returned from Hawai'i and had a wonderful time snorkeling in a special reserve along the coast  of Oahu that is protected by the State.  I swam with nearly all the fish that I keep at home in my tank and it was a thrill.  There were literally hundreds of fish in this cove, which is filled with coral reefs.  Can't remember the name but if anyone is interested I'll find out. When I returned I found I have a new problem with one of my three small Chromis.  It swims with the others, but then goes and hides in a cave or under a rock.  It is eating okay.  Isn't this pretty strange behavior for a Chromis?  I was away for two weeks but did a water change just before and 25% when I returned last night.  Tested water today and all parameters are fine.  I think this could be the Chromis who used to sleep apart from the others and who slept with my juvenile clown, who is now teamed up with my larger female.  I have been looking any signs of ill health and can find nothing.  Is he sick or what? <I don't think the fish is sick. Probably just making adjustments to the new space - can take a while sometimes.> Thank you all for all the help you have given me over the past several months.  You have enabled me to have healthy fish, and I sure have learned a lot.  I started with Bob's book but have graduated (but still refer to it) to your website. Hope you all had a great Xmas and have wonderful things happen to you in th e coming year. Aloha & Mahalo. Connie Cavan <Cheers, J -- > - More about the Chromis - Hi again. <Hello.> This is a p.s. to the note I just sent you.  Could this fish be afraid of my pygmy angel? <That is a possibility.> They used to play sort of a hide and seek game a couple of weeks ago, but maybe it wasn't a game. <Good observation.> Thanks. Connie Cavan <Cheers, J -- >

Large (old) Chromis Damsel Hi There: Just a quick (well probably long before I'm done) question. I currently have 6 green Chromis in my tank. The largest one is about three inches (biggest one I have ever seen ). <Me too!> For the last three days he has been sitting in the bottom corner of the tank (upright not on side). My heat fluctuates anywhere from 76 to 79 degrees throughout the day in the winter. Could that possibly be the reason ??? he looks fine just doesn't move. Is it normal for these fish to do this. ??     Thanks so much.. <Mmm, not normal... may be nothing... not temperature... Do just "wedge themselves in" amongst Acroporid and Pocilloporid stony coral branches in the wild... but might be "old age" catching up with this individual. Bob Fenner>

Breeding Green Chromis Hi! Sorry to trouble you, <No trouble at all.> but I was given this email address. Basically my green Chromis spawn every week. <Congratulations!> Any ideas on how to raise fry? <I would begin with rotifers. Damsels/Chromis are related to Clownfish. Hopefully, their larval stages are similar. I would research the needs for raising clownfish as a starting point. Joyce Wilkerson's book "Clownfish" could be helpful. Best of luck to you! -Steven Pro>

Green Chromis I have 2 saltwater tanks, one with 3 large (2-2 1/2") green Chromis and the other has 5 small (1") Chromis. In your experience, will there be any problems with combining them in 1 tank? Will they school or stay separate? <I have concern that the larger ones will actually bully the smaller ones to death. I would not recommend the mix> Thanks, Rich <best regards, Anthony>

Red Spot on Chromis Hello team! <whaaaasssupppp, Jesse? Anthony Calfo here> I have a newly setup 75G tank (about 3 weeks old) which I'm currently cycling with 7 Blue-Green Chromis (they've been in there for about 10 days). Presently, the ammonia level has just peaked and is starting to be converted into nitrite. The fish have been very active and healthy (brilliant color, great body shape, etc), and had been at the pet store for several weeks before I got them. I feed them flake food twice a day (about as much as they can eat in 2.5 minutes), substituting frozen brine shrimp once every three days. They all eat voraciously. Aside from chemical levels due to cycling, the tank parameters are decent: 1.023 sg, 8.3 pH and 79 degrees (since I could not get it cooler due to heat given off by my MagDrive pump, I just set the heaters to 79 and keep it there).  <all fine> The levels have been solid; there's been hardly any amount of fluctuation at all. My only source of concern, and as far as I can tell my only big mistake, is that I didn't do enough research before aquascaping the tank. As a result, I have several large pieces of lace rock in there. I've been contemplating taking it out, but have yet to decide whether or not this is necessary... <may not be necessary> Anyway, last night, I noticed a small circular red spot directly beneath one of the gills on one of the fish. It has grown slightly as of this morning. After reading just about all of your FAQs, it looks like a sore caused by bacterial infection of a wound. However, I have not noticed any damage before this. <whether infectious or caused by mechanical damage... do watch carefully... medicated food might be therapeutic. Water changes wont delay your cycle if you do not disturb the substrate...consider this> Also, I don't know how the damage could have occurred, since all of the fish are very peaceful with each other... The only source of strife at all is that, despite my best efforts, my cats like to sit on top of the tank and hang over the side looking in. The fish seem to be getting used to it, but they still get spooked when a cat first jumps up there. <yes... a bad habit that could have run one into the rockwork> Do you have any thoughts on what this spot might be or what I can do to help the fish?  <too hard to tell yet> I'll be beside myself if something I've done has caused them any harm Thanks for your help and for your website; it's without a doubt the greatest source of information I've found! - Jes <water changes and medicated food for now. Observe for three to five days, if worse be prepared to remove the fish to a QT tank for meds. Best regards, Anthony>

Chromis dimidiata I was trying to figure out if this fish is akin to the "green Chromis", i.e an effective "dither" fish that can be kept in small schools in the aquaria, or is this guy more like the dreaded domino in temperament? <My experience has been that all Chromis species are fairly peaceful.> Also, is Chromis cyanea a separate species from Chromis viridis, or are these just color variants? <No, these are different species from opposite sides of the world.> Are Chromis cyanea found in the Red Sea? <These are a Caribbean fish.> I'm confused by stuff that I've found on your website and elsewhere. Thanks. <Hopefully, I cleared up some of your confusion. -Steven Pro>

Chromis and Calcium Dear Bob & WWM crew, <cheers> You have helped me avoid heaps of learning through "experience". I've found that most journeys are less stressful when a map can be used... thanks for the "map". <with pleasure... do pass your wisdom along in kind> I want to add 5 small Chromis viridis to my 55 gal reef (48in.) and would like to know if this might be too much stress on the bioload or territory partitioning? <fine and peaceful fishes... they will fit with your below listed bio-load very well> The system includes 50lbs live rock, 2" fine sandbed & Reef Devil skimmer in sump. The bioload includes: 1 Brazilian Gramma, 2 Ocellaris, 1 Banggai, 4 serpents, 1 Sand Star, 1 Cleaner shrimp and various LPS & soft corals. Also, other than Kalkwasser, what additive will help raise pH without building much alkalinity? I'm running 7.9 to 8.1, the tank looks good, should I concern myself? Your thoughts would be appreciated! <I find Kalkwasser to be the very best at this with added benefits of saponification (improved skimmer performance) and phosphate precipitation. Best regards, Anthony>

Injured Chromis, Carpet Anemone, Corals Hey Guys salutations!.... <Salute!> I have a 150 gal reef tank with 3 Maldives clowns, 2 carpets, various SPS's, a school of 8 Chromis, and an Asfur. Today I noticed one of the Chromis' having one side of its scales ripped off by its gills. Its still active and eats with the school but is it a disease of some sort?  <tough to say but unlikely... if so it may be quite a condition. Fears here of a Septicemia. Without a clear photo were speculating here> The Asfur does magnificently disperse the school periodically in a fit of rage but I have yet to see him actually nip at one.  <statistically he'll succeed one day if he hasn't already...Ha!> My other thoughts are that I have lost 2 Chromis' to the carpets, I guess they stupidly float in there at night or something because on the afternoon after the disappearances my carpets spit out a meatless carcass of bones that suspiciously look like the frame of the Chromis. <indeed> Could this particular Chromis somehow brushed the side of its face against the carpet causing some blisters?  <possible... but carpets are so potently aggressive I would expect a kill> Everything seems normal, but I will make a water change today just in case. Give it to me straight...thanks!!!!  <OK... separate the anemone and other cnidarians (SPS corals and the like)... its a long term recipe for disaster (3-5 year plan). Noxious chemical warfare and the motile nature of the anemone> Oh yeah any good clubs to join in the Los Angeles area? <Absolutely... MASLAC at http://www.maslac.org/ I'll be speaking there in two weeks :) several other clubs in neighboring areas... SO CAL reefers, San Diego, etc> Regards, Dennis <best regards, Anthony>

Blue Reef Chromis Dear Bob & clones: <<I hope I'm not a clone... JasonC here.>> I just received 3 blue reef Chromis, which I specified to be no longer than 1" because of my miniscule inhabitants of my main tank. My problem is this: one fish is about 1" the other two are really big, one really huge (comparatively speaking). <<Even if you had gotten them in the size you wanted, surely they would never stay that size.>> Bob told me to add fish small than present inhabitants of my tank. They consist of a teeny dwarf angel, about 1-1/2", a royal Gramma (about 2 inches a clown about 1". I called flying fish, where I bought them (I had specified no more than 1", and he told me they would replace my pygmy angel if he died in battle. The fact is we have become attached to Bob and don't want he done in by a large blue Chromis. <<Chromis aren't typically that aggressive, and you might be surprised by the resolve of an angel who has been in the tank longer to hold its own.>> How serious is this problem? <<I would give it a shot and see... could be no problem at all.>> Flying fish suggested going to local fish stores and doing a trade, but the fact is local fish store usually have green Chromis, real small. What would you do if you were me? <<I'd give it a shot, if there is aggression from the larger Chromis, yank them and haul them down to the LFS and negotiate a trade.>> I don't know if I can even do a trade, but these guys would wipe out the present inhabitants. <<I'm not convinced.>> I am worried about my pygmy blue angel, because the largest one is bigger and the same color I don't want WWII in my tank. <<It may never happen.>> The guy from Flying Fish says he will replace my pygmy angel, but as I said earlier, we like him and don't want him destroyed. I didn't know reef fish came so big and hearty. I thought they were smaller. <<They come in all shapes and sizes.>> What is your fix on this situation? <<I wouldn't be that concerned.>> I live in the SF, CA area, and the fish stores don't have much and they are not very willing to order. Thanks for your help, Connie Cavan <<Cheers, J -->>

Chromis agilus Dear Bob: I have downloaded some of your wonderful pics you took in Hawai'i of the genus Chromis, and have been really trying to find a place to get 3 of the Chromis agilus for my 60 gallon reef tank. They would be the "stars" as the 3 other fish are 1 clownfish, 1 pygmy angel and 1 royal Gramma. I have tried all public sources and they are unwilling or unable to order these fish for me. Is there someone in Hawai'i you know who might ship to me, or someone here in California or elsewhere who has a contact. <Mmm, yes... have your shop, supplier contact Quality Marine or Underwater World in Los Angeles... they have regular HI shipments (weekly) and good rapport with collectors, may be willing to have their collectors send you some... though few of the Damsel species are collected from the 50th State (not enough pay to merit it... and the common techniques of capture and holding impose high mortalities on these fishes... or you might try Randy Fernley of Coral Fish Hawai'i... who has a nice retail shop on O'ahu and is a great collector...> I will be there over Xmas for my second wonderful visit, but don't think it possible to walk into a pet shop there and carry them on the plane.  <You could if someone had them.> I do look forward to snorkeling though and have your note to someone else who is going there soon. I am still painting and my next ptg is that calendar fish from last week, who thanks to you, is named Lorenzo. <Great!> My best - great diving, great pics. Connie Cavan <Many more to come my friend. Contact us when you're closer to Southern Calif. Bob Fenner>

Chromis agilus Dear Bob: Welcome back to the real world! <Yeeikes! Don't know if I can take it (Ha!)> I called Randy Fernley at Coral Fish in Hawaii and he was very helpful. I'm faxing him your photo of above fish and he said he'd have them for me (or would try to) when I am there at Xmas. <Great... his "pet name" is "Furry Slippers" (okay, mine is "Dogfish"... but Earl Kennedy's is "Lollipop"!). Randy is a fine person... and a great diver and asset to the trade.> I'm going to ask him to FedEx them to me if he gets them sooner. I gather he does his own diving. Fantastic! The fish stores here in San Francisco are really way below par for a city that "has it all". <Am surprised... there's a new one (can't remember the city, but an industrial park... with great walnut-like tank frames...) and a bunch of nice ones out in Sacto...> Thank you so much for following through. If the event happens, I will certainly let you know. <Hotay> My best wishes for you and the others who work so hard on your fabulous (really) website. Mine is listed above and is pretty much what one would see in St. Thomas, except for my fish project. I am up to ptg #3, named Lorenzo for some strange reason. Connie Cavan <How about Bob? Not the movie silly. Bob Fenner>

Chromis Hello Crew, <cheers, friend> I recently purchased a small school of 8 green Chromis. They currently sit in a QT. After initial observation I noticed one had a sore or bruise on its side so I quickly isolated this one and returned to my LFS for an exchange....no problems.  <they are sensitive fishes to handling> This morning on the fourth day of quarantine I noticed two other fish with the same sores as the one returned. But they seem very healthy swimming a close tight circle and are eating flake food.  <hmmm... some concern here for the contagious expression of hemorrhagic septicemia... highly contagious. It runs its course quickly if evidenced: all will be fine or all will be dead within a week if so> When purchasing there were several bruised fish swimming among the good. My question is could these bruises be because of the fish nipping at each other?  <not at all likely to this extent> the bruises are reddish with the scales slightly lifted or missing. What should I do? Treatment?  <yes... lets hope that it is a mild bacterial infection. Try Furazolidone and Nitrofurazone mixed meds at double strength daily for 5 days. A large jar of Jungle brand Fungus Eliminator crystals should do the trick nicely in QT> Many thanks again. Regards, Dennis <best regards, Anthony>

Chromis  Hi to all of you-I have another question. One of you suggested to me that because of the size of my tank (60 gallons) that Chromis would be a good option. I have downloaded pictures of some gorgeous Chromis - one is Chromis agilus and the other is Chromis ovalis. I cannot locate these fish anywhere- the viridis are available. I want to order three of them and have tried every online fish-selling place that advertises or that I have heard of. Is there somewhere I can order these fish directly or are they unavailable or what.  <both occur in Hawaii and although somewhat uncommon, at least the ovalis has been available in the recent past with regularity.> They are Bob's pictures, and the agilus is really beautiful. Thanks in advance for any help you can give. Connie Cavan <have you tried the Marine Center or Flying Fish Express? As you look for dealers... seek someone with a good Hawaiian or Micronesian connection (evidenced by C. multicolor angels, bicolor Anthias, Naso tangs, black tangs, potters angels and the like in stock) Best regards, Anthony>

Chromis vanderbilti  Hi gang! <Howdy Ted> I have a compatibility question. My LFS just got in a bunch of Vanderbilt Chromis and I think they're the neatest looking guys - much prettier in person than pictures. I would like to get a school of 5 but am not sure if that's too much for my tank and inhabitants. I've got a 55g tank with a pair of ocellaris, 6line wrasse, and a orange spotted goby (there's about 70 lbs live rock and 4 LPS - just to give an indication of how much space is taken up). Will they get along with the clowns since they're both of the same family? If that doesn't work is a fairy wrasse compatible with a 6line? <Mmm, had to go take a look at my pix, coverage: http://www.wetwebmedia.com/chromis.htm  What little I know re this species is actually stated there in a couple of sentences. I'd try a group of three individuals... hard to say re the current occupants getting along with the newbies... Some Clownfish species, specimens can be pure terrors territorially in such small volumes (a fifty five)... and do keep your eye on the six-line for the first few days... the species can also be troublesome. I would leave off with mixing in a Cirrhilabrus sp. here. Bob Fenner> Thanks in advance and have a great day! Ted

Green Chromis (numbers of the beasts) Dear Bob, A friend read that you should keep these fish in groups but only in odd numbers. Why???? <Sometimes called the "locker room effect" (by me at least), even numbers seem to lead to more fighting, bullying... between individuals. Having the "odd fish" results in having a bit more rest, ability to hide from the alpha individual/s> I have 5 in a shoal with no problems. He had 6 but one was attacked by the remainder and died. <Not atypical... but could be that the others had just already established territories that their resource would allow... no more room for another> Is the theory of odd/even numbers proven. It has certainly caused debate at my LFS (UK Marines -Roy Meeke) <No progress without conflict... not me this time, Nietzsche. Bob Fenner> Any answers would be appreciated. Kindest Regards, Stephen Tope

Re: Green Chromis Dear Bob <Steve> Many thanks for the prompt reply. I am busy upgrading to a 200 gallon system with 80 Gallon plenum sump. What number would be a good shoal for a tank of this size? <Five, seven, nine> They will be housed with 2 x Maroon Clowns, 1 Sixline Wrasse, 2 Lipstick Tangs, 3/4 Yellow Tangs, 1 Flame Angel and a couple of gobies. I am looking to make an impact with them. <Put them in first> Regards, Steve Tope <Be chatting my friend. Bob Fenner>

Red Spot on Chromis Hello team! <whaaaasssupppp, Jesse? Anthony Calfo here> I have a newly setup 75G tank (about 3 weeks old) which I'm currently cycling with 7 Blue-Green Chromis (they've been in there for about 10 days). Presently, the ammonia level has just peaked and is starting to be converted into nitrite. The fish have been very active and healthy (brilliant color, great body shape, etc), and had been at the pet store for several weeks before I got them. I feed them flake food twice a day (about as much as they can eat in 2.5 minutes), substituting frozen brine shrimp once every three days. They all eat voraciously. Aside from chemical levels due to cycling, the tank parameters are decent: 1.023 sg, 8.3 pH and 79 degrees (since I could not get it cooler due to heat given off by my MagDrive pump, I just set the heaters to 79 and keep it there).  <all fine> The levels have been solid; there's been hardly any amount of fluctuation at all. My only source of concern, and as far as I can tell my only big mistake, is that I didn't do enough research before aquascaping the tank. As a result, I have several large pieces of lace rock in there. I've been contemplating taking it out, but have yet to decide whether or not this is necessary... <may not be necessary> Anyway, last night, I noticed a small circular red spot directly beneath one of the gills on one of the fish. It has grown slightly as of this morning. After reading just about all of your FAQs, it looks like a sore caused by bacterial infection of a wound. However, I have not noticed any damage before this. <whether infectious or caused by mechanical damage... do watch carefully... medicated food might be therapeutic. Water changes wont delay your cycle if you do not disturb the substrate...consider this> Also, I don't know how the damage could have occurred, since all of the fish are very peaceful with each other... The only source of strife at all is that, despite my best efforts, my cats like to sit on top of the tank and hang over the side looking in. The fish seem to be getting used to it, but they still get spooked when a cat first jumps up there. <yes... a bad habit that could have run one into the rockwork> Do you have any thoughts on what this spot might be or what I can do to help the fish?  <too hard to tell yet> I'll be beside myself if something I've done has caused them any harm Thanks for your help and for your website; it's without a doubt the greatest source of information I've found! - Jes <water changes and medicated food for now. Observe for three to five days, if worse be prepared to remove the fish to a QT tank for meds. Best regards, Anthony>

Re: fish compatibility question Thanks for the ideas, Anthony. I was amazed to see you suggest a "school" of anything though; I thought I was almost stocked to the limit as it was...how large/small a school did you mean? It's only a 46, after all. <agreed... and very good intuition on your part. The Chromis damsels though are really quite exceptional. Very passive/peaceful, slow growing, hardy attractive. Chromis is the genus... check out many of the underrated species in this group in an atlas. 4-6 small ones (1-2" would be quite nice.> Could you please give the scientific names for the two types of Chromis you mentioned? Thanks again. <sure...check out the whole group at http://www.wetwebmedia.com/chromis.htm and pay attention to C. viridis and C. cyanea. Best regards, Anthony>

Quick Simple Chromis Question Bob, I've been thinking about purchasing some species of small schooling fish for my 90 Gallon Reef Tank. I've read all about the Chromis and I think that I have decided to add 3-4 small blue reef Chromis I think the species cyanea . Here's my question. I can order them online and pay for the rather large shipping charges (I've done this once already and all three arrived DOA from Saltwaterfish.com's) <Not a big fan of ordering/purchasing livestock sight unseen. Shipping charges usually come close to eating up all your savings and then if you have problems, forget about it (in my best Italian accent).> but I thought that I could buy this family of damsels in the LFS. Well, I've been to three stores and I don't trust anyone to tell me that those little blue "damsels" are from the Chromis family. How can I tell? <You can get several good pictures of these guys from the WWM webpage under Chromis. Also, these guys are Atlantic, so your LFS will have to have an Atlantic supplier. Be sure to quarantine these guys and all new fish for one month minimum. Mixing Atlantic and Pacific fish can cause all kinds of parasite problems. -Steven Pro>

Green Chromis G'day to all. <cheers, mate... Anthony Calfo in your service> I have a 120 gal FOWLR that is 2 months old. current inhabitant is a 4 inch coronation grouper (Variola louti). I was thinking about adding 5 green Chromises. I know that when the trout gets bigger he will find the Chromises to be a nice snack but for the moment while he is small I think they would be okay. <I honestly disagree... many "groupers" will kill this passive fish out of territorial aggression. I'd give them 2-4 months to live and advise against it> the reason I am after the Chromises is I like the way they school up and there doesn't seem to be any other fish that will school up in an aquarium. <goodness gracious... there are many fishes that will do so. Heniochus, Footballers, hippo tangs... too many to list> if there is please let me know. will 5 Chromises add to much to the bio load of my tank, I think 5 would be a good number, do I add them all at the same time to preserve the schooling nature or is it best to add just a couple over a few weeks. <for schooling fishes... buy and add at the same time> tank is 120gal,wet/dry trickle filter, skimmer (producing a bit of gunk everyday) amonia-0, nitrite-0, nitrate-5, calcium-460, kh-12, ph-8.4. <very fine> 30 pounds l/r with coralline algae which is already really taking to my base rock. <more live rock if possible... a very good investment> some Caulerpa (put in 2 days ago). only other fish I am going to put in is a panther grouper (I know he will get large to). when the trout and grouper outgrow the tank I am able to release them to their natural area (I have regular access to the southern section of the great barrier reef, Australia.) thanks for your help, the website is a great resource. <please DO NOT release these fishes... besides being illegal, it is irresponsible my friend as your fishes in captivity can cultivate strains of disease that can decimate native fishes on the reef on release. Furthermore, if you buy fishes from a pet store or mail order them from places that hold fishes from all over the world, your "native" fish might be exposed to an "exotic" disease in holding tanks that you cannot see. To release this into the wild can wreak havoc. It is a very serious concern my friend. Please never release ANY captive held fishes and obey the local laws if not the natural law. Best regards>

Protein Skimming Bob, I have a question about skimming. I recently upgraded my protein skimmer. I bought a Remora C (the water injection type). I have had it for a week and it has collected 4 times more nasty stuff than my old skimmer. I have had a little trouble with hair, green and red and algae. With this new skimmer I seem to be collecting a lot of green stuff. Will there be change in color of junk in my collection cup eventually? <Interesting question. Yes, likely> When I go to my LFS usually what is in there collection cup is brown thick stuff. I wondering if there is a cycle where all of the green algae disappears then the red algae will disappear. <There is, are... but there are definite different "skimmable make-ups" of different systems... much has to do with the types of life kept, foods/feeding, lighting, other filtration, type of seawater used, type/make of skimmer/technology...> I know I made the right move in purchasing this skimmer because of what it is producing and my water seems to be a lot clearer. I was told the best way to get rid of red algae is to lower the nutrient levels and skim it out. The hair algae I can deal with. Thanks for all of your help. One more question is it OK to have one green Chromis or do you absolutely need 2 or more? <More is better... social animals. Bob Fenner>

Chromis cyanea Hi, I've been a long time reader and of absolutely loved all your articles. Very helpful. I have a question about Chromis cyanea. Will these Chromis school? <Yes... do so in the wild> If so how many would you recommend for a school? They'd be in a 180 gallon. <A small, odd number... 3,5,7... Bob Fenner> Thanks a lot Jeff liechty

Re: Six-line wrasse Long time no email, been super busy... <I see> Just an FYI in case you are interested, but the Chromis didn't last long. I had ocellaris clown at the same time as the Chromis (didn't mention that last email) that is doing real well now. I think I've figured this out. The only thing the Chromis would eat were this frozen brine shrimp product, which I think was bad for the fish.  <As an exclusive diet, yes> The ocellaris would eat flake food. So for a week, this would be the case, Chromis only eating the frozen brine shrimp (I tried Formula One and Two and they ignored it). <Many good foods to try besides these> Both Chromis died shortly afterwards, no marks or cysts or any weird behaviour the night before. I'm now thinking they pretty much starved or had a bad reaction to this food (which I fed to all the other fish that died). I thought because they ate it so readily, that it was fine. But I now notice that anyone eating only flake food lives just fine, the rest die. Does that make any sense?  <In some situations, yes> I've since thrown that brine shrimp stuff away and now make sure that the pet store feeds them flake at least before I buy (paranoid now). Thanks -Jack <Some degree of paranoia is healthy in many/most human circumstances... Bob Fenner>

Chromis growth Hi Bob, I read the post from the guy who had the green Chromis for 10 months with no growth. <Ah, wish there was some easy way to retain alls email addresses...> I have three for over a year and they have tripled in size. They almost jump out of the tank when they see me coming at feeding time.  <Very well trained!> My wife calls them piranha, as they always attack the food first. When I got them they were under an inch and now they are pushing three inches. I always wondered how long they lived. Happy to hear I should have them for at least four more years. On another subject, how long do cleaner wreaths live? <Genus Labroides wrasses generally don't live for long in captivity, but the ones that do "make the transition" to aquariums have been known to live for a handful of years> I have had one for several months it is always very active, and constantly cleans the other fish. It is right behind the Chromis come feeding time. I have read some of your posts and it appears people have trouble keeping them. Do you know the reason? <A combination of phenomena... if I were to try listing the more important ones: shipping, holding trauma, collection damage, mouth damage totally (from bumping into tank sides, bags, nets...), "stress", a paucity of "customers"...> I really like the little guy and want to make sure I can keep him in top health. Thanks for your continued support in this challenging hobby. <You are welcome my friend. Thank you for your continuing participation and sharing. Bob Fenner>

Chromis Viridis Bob, one of my most favorite SW fish are the Blue/Green Chromis. (Chromis viridis) Small, peaceful, hardy and oh so beautiful. (a very under-rated fish IMHO). <Agreed. I have a nice cover shot on this month's Das Aquarium magazine of a trio> How long do they live usually? <Probably a handful of years in captivity... do know of a few instances of 7,8,9 year old individuals> I have seen very large 3 to 4 inch "Big" blue/green Chromis! I have had mine 10 months and bought them around 1inch. They have not grown very much in that time so I am wondering at how long will it take to grow them into the whoppers I have seen.  <Not just a matter of time... as you likely know> They eat everything I feed them (a very varied diet for sure) and they eat often. I just thought there would be more growth by now. Water perimeters are excellent, food is varied and tank conditions seem as good as could be. Slow growers or am I not doing something right? <Very large systems, water movement, lack of metabolites in their water, almost continuous feeding... are some of the predominant factors. Please read: http://www.wetwebmedia.com/optgwth.htm Bob Fenner> Zimmy

Re: Hey Bob ;)(Trachyphylliid, Pomacentrus, stocking) Hey, I hope that my gratification is not getting too much for you, but again, thanks so much for your time, my friend. <"The only true gift is a part of thyself"> First, the brain coral appraisal. Not a brain coral at all (of course you knew that) <You are right... am becoming quite transparent... am glad for this> , it is a "Super Green Wellsophyllia" <one more "l"> To recap the situation with this guy, he is about half the size he was when I originally got him and his colors are not quite as radiant. . . He also looks quite a bit "harder" as before he was light and fluffy looking Is there anything that I may do right now? <Mmm, check on biomineral, alkaline content of your water... perhaps feed the colony... See coverage as per old family affiliation/classification, Trachyphylliidae: http://wetwebmedia.com/trachyphlliidae.htm> OK, new issue. In my 90 gallon (75 g plus 30 g sump) I have approximately 19 inches of fish, and the rest reef clean up crew. From my research I have about 10 "inches" more of fish to stock the tank before I can call it a completely stocked reef. Am I on? <Sort of... "completely stocked" is a subjective reality... It's not stocked till you believe it so... It is currently stocked IMHO, but you could add more.> I am also looking forward to having some schooling fish of some kind (in this case 5 small fish to finish off the stock). I did read several of the damsel articles on WetWeb. . . I was hoping for more FAQs regarding the "Lemon Damselfish" for a reef environment. <Please write them and I will post> But here's where it gets interesting -- just attempting to properly identify this guy. On FFE he goes by "Abudefduf aureus" In Aquarium Fish Magazine he goes by "Pomacentrus moluccensis." In the WWM you match what Aquarium Fish Magazine calls it.  <This is a/the fish. Maybe check the current i.d., taxonomy on fishbase.org> If this species is appropriate for what I am looking for (a colorful splash of yellow schooling fish, as I have decided not to go with the Yellow Tang (too aggressive), <Mmm this Damsel's about as aggressive, a bit smaller...> that will be hardy and easy to take care of, and like to be seen. And most of all, are they really DARK YELLOW, like the Yellow Tang?  <Check the images out on fishbase... this Damsel, like many, changes with age/growth> Or are they pretty dull? And about its identification. On FFE they don't offer a pic with this guy. The last thing I want is to order him and be stuck with a bunch of destructive goldfish! You know what I mean. <Maybe> I have other questions, but I attempt to keep them in species order so that you can properly file them into your priceless knowledge FAQ database. <Our database> Look forward to talking again in the next few days. I'm getting the aquarium stocking itch again!! Kindest regards, Rich <Be chatting. Bob Fenner>

Blue Devil Damsels Hello again, Thanks for getting back to me so quickly regarding my clownfish and coral question. I forgot to ask you about my blue damsels. One in particular I have had for about 4 and a half years. She seems to be fine, but within the past few months, I've seen something quite peculiar. I saw her floating belly up and assumed she had died, but as I neared the tank, she sprang up and swam away. I've witnessed this countless times now. She stops swimming, her fins become erect, she flips belly up and drifts with the current and a second later she's alert and swimming around. Like she had a mini seizure or something. Any ideas? <Mmm, this sort of "strange behavior" could be due to fatty degeneration inside the specimen (and hence spatial disorientation), some specific diseases (like Whirling), but in this case more likely due to "play"... A note here: simply going to the surface of the water is a "novel" experience for this species in the wild (they would be eaten almost of a certainty), so it's not so surprising to find that one/they might adopt other seemingly bizarre behaviors...> Lastly, both my blue devils (especially the older one) seem to change color when stressed. When the older one becomes defensive or aggressive, she gets white patches throughout her body. When the fish she is threatened by leaves, her color automatically returns. I've started to notice this with my younger blue devil also. Any thoughts about this? <This happens. Good observation> Sorry about the lengthy message. Thanks, Ben Mendez <No worries, be chatting. Bob Fenner>

Chromis viridis - blindness Hello Robert, Recently, one of my green Chromis went blind. In my desperate search to learn the reason for this, I have only managed to find two references, your mention of it on WetWebMedia, and the observations of a one DBW (aka: "the Caretaker") of www.ozreef.org. <Ah, excellent company... and good searching on your part> At any rate, I was hoping that you might be able to provide me with more information regarding this condition. How does it arise? Do I need to worry about the other members of the school contracting this disability? Is there a cure? Etc....etc....etc.... <In damsels this sort of complaint generally stems from either nutritional deficiency or disease (parasitic, infectious). There is some chance that this animal has age as a co-factor going against it as well> At this point, the blind Chromis seems to have stabilized and seems to be getting enough to eat despite the increased difficulty for it to actually locate its food. Needless to say, I'd love to see it recover and any help/info you can provide would be most appreciated. <Do try adding a vitamin and iodide preparation to these fish's foods ahead of offering. If the nutritional component is at play here this may effect a reversal. Good luck my friend. Bob Fenner> Best Regards, Steve Rider (a concerned reef keeper in Munich, Germany)

Reef Chromis beyond Green? Robert Fenner: There seem to be many types of small Chromis that would be suitable as fish for the reef aquarium, but only viridis, cyanea and occasionally dimidiata are available in the trade. Why? <I often call this the "founder" or "flounder effect"... Yes, there are MANY more suitable (in fact much more suitable) species of fishes, non-fish livestock that can/could/should be utilized in the ornamental interest... as an old-timey industry person who visits collection, breeding sites all year long I'll tell you... mainly "key" species are targeted... as they're already known to be "good sellers", "in demand"... Amazing, this is the principal reason why we see so few "new" species offered~!> Or am I just not shopping at the right LFS or website? Do you know of anyone who offers other types of reef-safe Chromis for sale? RJS <Try the fine folks at Marine Center (dot com)... and ask them in turn where you might go... There are "contaminants" from time to time that "show up" in shipments as well... Bob Fenner, who says, come travel diving with us and pick up your own!>

Re: Reef Chromis beyond Green? Thanks for the info. I can see why the "flounder effect" would apply to the old-line LFS pet store trade -- but the Internet trade would seem to open new markets for the bold supplier.  <Ahh, yes... We could use people of your caliber and enterprise in our industry... unfortunately the remuneration and prestige are not high... And the Internet companies have absolutely nothing, zero, nada to do with what gets caught, shipped from the wild... the structure of the trade is such... However, with enough "bottom up" demand for livestock... new species are added... over a few years time... sort of like turning a big ship with a small rudder... And the all-important, opening up of new collection areas... like airline service going into some place that has viable species, abundance, governments that want to see their resources used properly... these sorts of influences... once again... time frames... years...> Let's hope some adventuresome web/dotcom shipper will break the trend and supply some new varieties.  <You would/could have more effect by taking photographs, writing a "happy story" about the suitability of said species... this is, um, what yours truly does, has done the last few decades> There is a ready market. I am not the only one out here tired of the same old same old -- sounds like a financial opportunity for somebody! <Indeed my friend. You are correct. Bob Fenner>

Tail rot (wherefore art thou causes?) Hello Mr. Fenner, I have just introduced 3 green Chromis damsels back into my system after leaving the system fallow for a month due to an ich problem. After 36 hours the tail of one of the damsels is nearly gone and the base is pink and irritated looking. What could this be?  <Bunk quality Damsels plus stress likely...> They were quarantined and received a dip of freshwater and Methylene blue just prior to reintroduction. The other two look and act fine. thanks Steve B. <This one "got nicked" somewhere along the line... Take a look on the Damselfish pages on the site www.WetWebMedia.com and read the "Selection" area on the general Pomacentrid piece... many Chromis and other damsels lost in the early introduction phase. I would NOT "treat" this system per se... with chemicals, but would consider adding a biological cleaner. Bob Fenner>

Chromis viridis questions... Hello! A few days ago, I asked you for suggestions in keeping a damsel tank and your response sparked a few questions... One of the genus you recommended was Chromis. 1.) Can I keep Chromis viridis in a school? (I only have a 60-gallon hex. tank with live rock but heard they are relatively peaceful as far as damsels go. <Yes, best this way... three or five individuals> 2.) I also read that they are more susceptible to eye diseases (resulting in blindness) than other damsels. Is that true? <Not IME> 3.) What fish should I be weary of putting in with this school? I would like to add color, but want to be conscientious of the setup. <Tank really too small for this> Thanks so much for your help! I can't remember the last time anything has captivated me like this hobby! Unfortunately, I've had a string of bad luck and that's why I have decided to stick with damsels. At least for now. <Will help insure your success, lack of such strings from now on. Bob Fenner> Declan Procaccini


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