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FAQs on Dartfish Compatibility

Related Articles: Dartfishes, CA: Family Microdesmidae, the Worm- and Dartfishes by Robert Fenner and Anthony Calfo Gobies

Related FAQs:  Dartfish 1, Dartfish 2, Dartfish Identification, Dartfish Behavior, Dartfish Selection, Dartfish Systems, Dartfish Feeding, Dartfish Disease, Dartfish Reproduction,

Hi Bob,
 I have 2 royal grammas that are a pair and I really would like a pair of Red Firefish, but I read on the Internet they would fight is this true? If they will, is there anyway around the problem?
Many thanks

Grammas and most species of Dart Gobies (family Microdesmidae) unfortunately do occupy about the same habitats, and often are at odds if kept together in captive systems. There are a few techniques, approaches to improving ones chances of co-mingling them though. One for certain is the size of the system itself. Given enough bottom area, with mixed size substrate (to 'hold up' burrows) and rock work strategically placed to block their viewing of each other, almost any kinds of life can be housed together. Another notable factor is introducing both species at the same time, toward lights out/evening time to negate either having becoming familiar with their surroundings, establishing territories'¦ excluding the new-comers. If this last isn't possible, rearranging the hard elements of the aquascape is advised just prior to introduction of new stock.
            Other than these preventative measures, there is no substitute for your diligently observing livestock interaction, and being ready to separate aggressors. Oftentimes, placing the bully-ies in a floating colander (plastic of course) in the system for a few days will go a long way to reducing inter-species aggression.

Purple Firefish Compatibility? (is a timid little fish…conspecifics aside) – 04/25/13
Hi there folks!
I love the forums and read till my eyes cross and words blur!
So much great info.
I was wondering, I have a Biocube 29 gallon with about 20 lbs of live rock. Right now I have two Percula clowns,
<<Mmm…this tank is a bit small for such, in my opinion.  Would prefer to see these in 40g+>>
a small Cardinal and one Blood Fire shrimp.  Would adding a purple Firefish work in this setup?
<<These are quite timid fishes…easily harassed/stressed…with dire consequences.  I think the Clowns would pose a problem re>>

I've had my eye on one for quite some time now and haven't seen much in the way of compatibility of these little guys. The people at my LFS say I shouldn't have any problems, but wanted a second opinion from another source (that doesn't have some sort of stake in this).
<<You have it [grin]>>
If Firefish won't be a good option, do you have a recommendation for another fish?
<<Hmm…  If you must, perhaps a small Dottyback like Pseudochromis porphyreus.  Small and colorful…and just pugnacious enough to survive/coexist with the established Clowns.  Though such behaviors (on both the Clown’s and Dottyback’s part) are very often exacerbated in small confines>>
Thanks so much!!!
<<Happy to share…  EricR>>
Re: Purple Firefish Compatibility? (is a timid little fish…conspecifics aside) – 04/26/13

Thanks so much for the info!!
<<Quite welcome>>
I'll be doing my research on the Dottyback.
Now, my last question: I'm finding conflicting information on feeding a Fire shrimp.
Right now I feed a Spirulina 20 flake to my tank members, and every couple of days adding some thawed vitamin enriched brine shrimp.
<<I very much suggest expanding this diet to include thawed frozen Bloodworms and/or Glassworms, Mysis Shrimp…and the very nutritional and palatable New Life Spectrum pelleted food (I suggest the 1mm pellets here).  You don’t have to feed all every time (though I do suggest a pinch of the pellets at least once daily)…and several small daily feedings are better than one big feeding…but your fish, indeed your whole system, will benefit from a better diet than what you currently describe>>
When I feed flake alone my poor shrimp comes out of his cave excited for food, but seems disappointed when he finds it's only flake and slinks backward into his home. I feel guilty!!!!! Should his diet be different?
<<It should, as mentioned>>
What should I be feeding him differently?
<<All of your tank inhabitants will enjoy and benefit from the foods I mentioned…the shrimp will especially enjoy picking the pellets from the rock/substrate>>
<<Always welcome…  Eric Russell>>
Re: Purple Firefish comparability??   5/17/13

Well, I took the leap and got a Pseudochromis porphyreus! I love him! He just went into the main tank yesterday and seems to be adjusting well and getting along with everyone else (except for the fire shrimp who only wants to clean him which Dottyback wants no part of!)
I feed New Life Spectrum 1 mm pellets each morning and frozen meaty foods (Mysis, brine, krill etc.) in the evening. I noticed he would love to eat the pellets, but they're just a tad to big for his small little mouth.
<Look for smaller sizes... The 1 mm. should work>
 He cant/isn't able to swallow them. Will he be ok just eating the meaty foods in the evening till he grows large enough to consume the pellets?
Thanks so much for the suggestion of this little fellow, he's a joy to watch and I think he will fit right in with the fish family!!!
<Ah good. Bob Fenner>

Nemateleotris magnifica, stkg./sel., comp.    3/10/13
What are your thoughts on a group of 5-7 of these in a 210gal with ~300lbs of Live rock forming lots of caves?
Brad Chymist
<As long as there aren't other fish and invert. species that cause these Microdesmids trouble, I think you'll have a fab display amongst them in this setting. Bob Fenner>

Goby <Microdesmid> Compatibility - 1/25/13
Hi guys, thanks as always for such a useful and informative site. I currently have a 120 gallon FOLWR tank with 4 tangs, a blue face angel,
<Needs more room than this>

a couple of clowns, a six line wrasse and a fire goby; there is a lot of live rock. My question is this...I currently also have a quarantine tank set up with two Zebra Dart Gobies in it, happily settling in to things. If I were to add these fish to my main tank would the two types of Firefish
<There should be enough bottom space for both here>
Is it worth the risk?
<Only you can answer this... but the tangs, angel... a bit too busy in this volume for gobies. Bob Fenner>
Thanks so much. Matt.

Two spot/candy hogfish and Firefish compatibility    1/11/13
Added a candy hogfish to my 58-gallon mixed reef. After two days, Firefish dug a new hole and went into hiding.  Comes out briefly to eat. Never saw the hogfish chase or harass him. Am I going to have to get rid of one of these?  Thoughts?
<Not unlikely with the Firefish (which species; these are social animals... pairs/duos or groups depending on sp.... and need a good deal of bottom space, mixed substrate for burrowing... See WWM re Microdesmids)... that the Bodianus is either harassing the one, or that this is how it appears to it... Not a good mix in a small/ish volume... less than a hundred plus gallons>
Thanks. You guys are great.
Tim Silver
<Keep reading! Bob Fenner>
Re: Two spot/candy hogfish and Firefish compatibility    1/11/13

Okay, the hogfish goes to the LFS today--if I can trap him.
<Ahh! Two nets... good hunting. BobF>
Re: Two spot/candy hogfish and Firefish compatibility    1/11/13

Caught him with a homemade bottle trap.
 Took about 3 minutes and he was on his way to the LFS.  Do you think a citron goby would work with the Firefish who, by the way, was out of his hole before I got out of  the house with the hogfish.
<Mmm, yes; highly likely so. BobF>

Sexing of Nemateleotris magnifica  12/31/12
I have been searching for a way to sex Firefish with no luck.
<Mmm, have observed Microdesmids in the wild, captivity... no distinctive sexual dimorph- or dichromat-ism>
 I found one reference that says females may be more slender.  I have had three in qt since mid November, and am hoping for a pair in my 29 gallon reef.  They are eating Spectrum pellets greedily, but the three hang out together and I have seen no evidence of one being left out of the loop.
<Ah good>
 I am hesitant to add all 3 because of how difficult one would be to remove, which is the only reason they are still in qt.  I have space in a 65 for the odd man (or girl) out.  If there is no good way to tell, how long will they take to sort this out themselves?
<Already would have>
  I would really like to get my qt ready for other additions :)  If you would like to see a picture there is one on my blog over in the Wet Web Media forums. 
Thank you!
Matt Bowers (muttley000)
<Thank you for sharing. Bob Fenner>

Firefish Nemateleotris magnifica  Stocking & Compatibility     11/28/12
Thank you all for past advice and for future guidance, as it is always appreciated!
 <Ah, welcome>
I have a stocking question on Firefish.  I would like to tell you my tank setup and then give a few scenarios.  I have read, even on this site, many contradicting opinions (gasp) on how many can/should live together.
 I have a 55 gallon aquarium, with 60+ pounds live rock, 4” sand bed, 10 mushrooms, 1 toadstool, 2 Ocellaris Clownfish, 1 peppermint shrimp, 1 urchin, 1 brittle starfish, several snails and blue leg hermit crabs, a large canister filter with UV light, HOB protein skimmer, and water movement of 425 gph powerhead + 250 gph from the canister.  To the examples… 1) Can I, should I, would it be wise to keep Firefish with the Clownfish?
<Mmm, if there "peaceful" (as most specimens of this species are) there should be no problem in this size/shape system>
 Right now the 2 clowns are about 1.5” each.  2) How many Firefish can be or should be kept in a 55 gallon aquarium?
  I’ve read only one, also that pairs are best, that they like to be in groups of 3 or more,
<Mmm, no; not this species. Almost always encountered in duos/pairs in the wild. Don't like close conspecific neighbors>
 and that any more than 1 will just end up being 1 through attrition.  3) Is there anything wrong with this stocking
scenario… 2 Ocellaris Clowns, 4 Firefish, and 1 Royal Gramma? 
<The Gramma could turn out to be too mean toward the Microdesmids... and I'd just go w/ the two Dartfishes>
Could I have reasonable expectations of success and happiness?
<... see WWM re compatibility (FAQs) of all mentioned. I'd go w/ what I've listed above>
 4) What if there was a Blue Damsel that hypothetically completely left alone the new Firefish, would the Firefish likely starve itself just because the damsel eats so quickly and moves fast?
<Not likely; no>
 The only other note is that the aquarium is about 4 years old and established aside from being moved a couple months ago.  I greatly appreciate any experience and thoughts you can share on the matter.
<Welcome. Bob Fenner>

Surprised with a fish and coral, Firefish/gramma incomp.       9/24/12
Thanks for all the years of help first off. I was wondering if you could help me, I have a small 14 gallon tank that I've been taking care of for about 4 years since I got it when I was 16. It was a personal hobby that pretty much only I found interesting, but after four years of effort I've established a beautiful reef tank with many different types of soft coral and one purple Firefish. Recently, I came home and my mom, who's taken a sudden interest in my tank, said she got me a surprise fish and coral.

At first I was happy until I realized that she has no idea bout the dynamics of a tiny reef system and I was terrified that she had got me a tang or a lion fish. While it wasn't that bad she did purchase a royal gramma which I know would appreciate a larger system.
<Not likely to get along w/ a Firefish in such a small volume>

Unfortunately I cannot get it out, and I'm worried that it'll start fighting with my Firefish, since he's had free reign over the tank for about a year. Is there anything I can do to help keep the peace and keep them as comfortable as possible?
<Not really, no. Either they will co-exist (not likely) or one drive the other (likely the Gramma will win) out of the tank, life>
 Also she purchased a meteor shower Cyphastrea which I knew nothing about until I looked it up, but I've seen conflicting reports on how much light it should get and how much to feed it. Any tips would be greatly appreciated.
Thank you so much,
<Do search, read re these two on WWM. Many people have tried this combo... doesn't often work. Bob Fenner>

Mixing dart fish    4/18/12
Hi crew, my question today is about whether multiple species of dart fish can be mixed in my 65 gallon reef tank.
<Mixing species of Dartfish is not advised with larger tanks being the occasional exception.>
 I currently have 2 Ptereleotris evides and was wondering if they would be compatible with a pair of Nemateleotris helfrichi .
<They are going to fight it out in that small of a tank. One species per tank is the safe bet.>
Thanks in advance for your thoughts.
<Quite welcome>
Fwd: Mixing dart fish    4/18/12

Hi crew, just following up since I did not receive a response on the query below. Would really appreciate your thoughts.
<I apologize for the delay, response sent to previous email. There must have been a mix-up on our end; I saw both emails for the first time this morning.>

Zebra Dartfish    2/5/12
Hope your <you're> enjoying the Superbowl. 
<Just the ads>
I had a couple questions.  I just bought a zebra Dartfish
<A social species. Really only lives well/long in groups>
and put him in my 10 gal. QT tank.
<Keep this tank covered!>
 I read that certain Dartfish do better without quarantine and was wondering if I should place him directly into my 37 gallon main tank?
<Mmm, yes... but this is a tad small space wise>
 Also, I only purchased one and immediately regretted not buying a mate for him.  Do you think a pair would do better in a 36 gallon with one tank-bred Ocellaris clown, with about 25 lbs of live rock or is it too late to buy another? 
<I'd buy two more. Bob Fenner>
Re: Zebra Dartfish    2/10/12

Thanks for your advice about the zebra's.  I went back to the LFS and luckily they still had two more so I bought them up quickly.  I have been reading articles on the website and am thinking a nice hang on refugium would be good to create some zooplankton for them.
  Not having a lot of money I searched the internet and found a 14'' hang on with protein skimmer for around $100.  I'm assuming it isn't top quality, but I'm at a loss as to what direction I should go.  Looking for some much needed guidance.  Thanks!!
<Mmm, there's always the WWM site... Read here:
and the linked files above... BobF> 

Re: Zebra Dartfish... was stkg., now comp.    2/18/12

Thanks for all the advice as of late. My zebra darts are getting along great, and my clown seems to think he is part of the group.  I ordered a small in-tank refugium to produce
some plankton for these guys which I am sure they’ll appreciate.  My next question is I am looking to add one more small fish down the road.  I would really like a Jawfish of some kind.  I find them incredibly entertaining.  My question is would a problem develop between the zebra Dartfish and the Jawfish.
<Mmm, this is still the 36 gallon... A smaller Opistognathid might fit, might not>
 Would it be better to go for a goby or blenny of some kind?
<A little more likelihood of compatibility depending on species>
 Also, the tank contains 2 Emerald Crabs, who seem peaceful so far.  Thanks for the great site!
<Welcome. BobF>

2 questions/firefish compatibility and assessor issue  10/31/11
Good evening,
I have spent an hour on your site tonight researching this question and I have learned a lot but thought I would check with you all anyway. (For reference, I have kept purple firefish for years, always singly). A friend of mine is moving and has broken down her Nano and unexpectedly I have a beautiful Helfrich firefish. He is in my 29 gallon Nano. He is fine, already eating, but there is a red firefish already in there (has been there for about 1 year). I am reluctant to pull the red firefish because I would have to take him to a store or throw him in my 90 gallon that may be a tad rough--wrasses, a butterfly, an angel==however, I will do so if you think it best.
Obviously the red one is a much less valuable fish.
Right now they are completely ignoring each other (have all day) but it appears from your site that could suddenly change.
Although elsewhere on your site it states that various firefish can live together,
<If there's room... not here likely>
there also seems a lot of evidence to contradict that. ( it also seems like it might be the story of the Banggai cardinals that I had in my 150 gallon, where I started with 4 and after a year or so, I had two and then for the past three years, just one (alpha) Banggai. )
Thanks you guys, I am going to cross my fingers and risk one night until I hear from you.
Second question, my yellow assessor (have had him 2 years in afore mentioned Nano) has developed what I will call whiskers. They almost look like the little "antenna" that are on a tailspot (or similar) blenny but they are new and clear and very small. He is still eating and seems fine but wanted to check. Let me know if you would like a photo.
<Do please send along... most likely these "whiskers" are spines from Bristleworms>
I appreciate all you do.
Thanks again.
<Welcome. Bob Fenner>
Re: 2 questions/firefish compatibility and assessor issue 11/1/11

Thank you for your reply. (Not sure what the "Mmmm" means. I refer to replacement value only. )
<Is my interminable mumbling statement... cogitating furiously if you can believe such>
The two now seem bonded but who knows if that will last.
<Quien sabes?>
"Whiskers" from assessor now gone but a number of Bristleworms removed from tank. I think I removed all but one. I appreciate your help as I could find nothing on this in any of my literature. (fish interaction with Bristleworms I mean)
<We have a few choice pix... don't recall right off where they are; but this situation is not uncommon. Cheers, BobF>

Helfrich Compatibility 8/14/11
-Greetings wet web media crew.
<Hello Kathy>
I have a quick question for you , I'm in then process of setting up a 50 gallon tank around my Helfrich fire fish. It will have lots of live rocks and caves for hiding. My question is, will the Helfrich be compatible with
either a Swiss guard Basslet or a candy Basslet?
<Should be fine, but take a heavy wallet with you when you go shopping for the Candy Basslet (Liopropoma carmabi). I've seen these go for as much as $900.00.>
<You're welcome. James (Salty Dog)>
Re Helfrich Compatibility 8/14/11
I know........ Might settle for the Swiss guard Basslet instead! Haha!
<Yes, that is the poor man's version of the Candy Basslet.>
Thanks much for your quick reply.
<You're welcome. James (Salty Dog)>

Firefish Compatibility 3/16/10
<Hello Mark>
I have been reading your answers every day for years and it never gets boring. Thanks for your efforts.
<You're welcome, and glad you enjoy/read our dailies.>
Even though I am an experienced marine aquarist, I fell victim to an impulse at my fish store a while back. I purchased 3 Firefish, who have been in my quarantine tank for over 5 weeks and are doing well. All three hang out
together and even hide and sleep in the same protected area. No problems with fighting or aggression with one trying to establish as an Alpha fish.
The fish really seem to get along well at least now. I bought these fish for my 90 gallon which has an abundance of live rock and 2 Perculas (2 inch plus), a purple tang (3 inch), a Sixline wrasse (3 inch), and a lawnmower blenny (4 inch). Everyone gets along famously. My question is what do you think will happen when I introduce the 3 Firefish into the tank? Can I expect aggression or will everyone continue to chill and accept their new neighbors? I have spilt feelings about introducing them in my main tank or just keeping them in the quarantine tank and converting it into a second tank. Your time honored wisdom is appreciated.
<With your present inhabitants, they should get along well. Your abundance of live rock will provide the necessary safety zones for the Firefish. Since the Firefish are not aggressive eaters, you will need to ensure that they are getting enough food.
You may want to read the Firefish/Dartfish compatibility FAQ's before making your decision.
Thank you.
<You're welcome. James (Salty Dog)>
Mark Hill

Firefish Aggression -- 04/18/09
Hi Crew,
<<Hey Samuel>>
Just relaying an experience.
I have a 24 gallon Aquapod with a Firefish and a chalk bass. When I was at an LFS they had 2 Firefish on sale.
<<Uh-oh'¦know where this is going.>>
They had been in the store over a month. I was tempted to buy them even though
I had one in residence which usually is a problem. I fell for my temptation.
So I put them in with tank lights off (no qt). The next morning all 3 were out front and seem to be ok during the feeding.
During the day I would see them and there was no interaction. The next morning I only saw my original Firefish and even during feeding the other 2 did not show up.
<<And so it begins.>>
Then the next day the original one was there plus one of the new ones who now had a
slightly shredded tail.
But the second new one did not show up. It has been a few more days and the second one has not been seen.
<<Is likely 'gone' by now>>
I guess he was dispatched and I now have a pair.
<<We can hope (that you have a true pairing)>>
What surprises me is that I never saw any aggression.
<<Not unusual with this fish in my experiences. Other than a few ominous looks/advances toward the subordinate individuals made in 'public', it seems most of the actual mayhem takes place 'behind closed doors' so to speak>>
I thought that if there was a problem I could intervene and remove the aggressor but it did not work out that way.
<<Indeed'¦ As mentioned, your observation/experience is not atypical for this species in my opinion. And though I also think your tank is a bit small for what you attempted'¦I've not seen much success re social groupings of these fish in larger tanks either>>
Thanks for listening.
<<Welcome'¦thank you for sharing. EricR>>

Multiple Species of Dartfish in the Tank... � 11/21/08 Hi Crew, <<Hello Jon>> I have done all my reading and am still totally at a loss as to what to do/expect. <<Oh?>> I have read that different species of Dartfish are compatible/not compatible in the same tank (34 Gallon tank w/ 5 Gal fuge). I have also read that you should keep them in small groups, you should never keep them in small groups, only mated pairs are ok together, even mated pairs will fight each other, etc. And that is just from your site alone!! So please understand my confusion'¦ <<Mmm, indeed'¦ Aside from differences of opinion/experience, some of the contradiction likely stems from the fact that these fishes are generally quite social in the wild, but with only a couple of species remaining so in the aquarium (have a look at the December issue of Tropical Fish Hobbyist for an interesting and informative article on these neat little fishes)>> As it stands I have a purple Firefish (Nemateleotris decora) <<Probably the more aggressive of the Dartfish species>> and a zebra Dartfish (Ptereleotris zebra) in the tank. I have no plans to get any more fish, and since the N. decora pretty much hovers near the bottom of the tank, and the P. zebra stays near the top of the water column I figured it would be safe. <<Agreed'¦ I think these two species are dissimilar enough that there shouldn't be any serious issues. Now, if you had added N. magnifica rather than P. zebra, the situation likely would be much different (worse)>> I just wanted to check with you guys, as I expressed my concerns about mixing the two to the LFS. They said that they thought it would be fine and if it turns out that they don't get along, the LFS will take the P. zebra back (pretty great of them, I think). How could I turn down such an offer ;) <<Indeed'¦ Though like your LFS, I do think you are fine here>> They are getting along right now and I am inclined to keep the Zebra, <<I would>> but am I asking for trouble down the road? <<Not in my opinion>> Thanks, Jon <<Quite welcome, EricR>>

Firefish compatibility 04/13/2008 Hello! <<Hello, Andrew today>> I really can't tell you how much I appreciate your one-on-one help and your awesome site. I have spent countless hours on it in the past couple of weeks! :) It means a lot in this hobby to have someone whose advice you can trust; someone who cares and doesn't think they are "just fish." Which is why I'm coming to you to bug you with one (ok maybe a few) more questions! <<He he he...bug as much as you like Mandy>> I think I'll be set for a while after this one. My empty tank was really depressing me and I drive by a great aquarium store on my way home from school on Thursdays, and they just happened to have a beautiful school of Firefish. I had already done some research on them since I thought one would have made a good tankmate for the Jawfish. The guy working there asked me how big my tank was, to which I replied "20 gallons," and he said I should get three of them because they like to school and he would cut me a deal...I told him I would just try one for now. So I brought "her" (it looks girly :) home. I acclimated her with the lights out for a while and she settled into the PVC burrows I made. As soon as I turned the light on she came out and out she stayed, hovering around the middle of the tank. She even ate right away! (Yay!) <<Off to a wonderful start it seems>> When I turned out the light last night she went straight to her burrow bed. She ate again this morning. I am so happy to have a fish that seems to be doing well! Now for my questions: I read all of the articles about Firefish on your site last night, but found conflicting info. Some cases it seems like the Firefish stress (and possibly even die) because they are alone and pairs are recommended, and in some cases pairs were deemed to risky. I'm guessing with my 20 gallon tank that I should stick with one, but will she be stressed out by being partnerless? <<NO, have seen many singular Firefish in a tank without experiencing any issues>> I would love to get lucky and have them pair up, but I wouldn't want them fighting and hurting each other. <<In my opinion, you could get away with a pair in a tank of this size>> I certainly wouldn't go with the 3 <<Agreed>> that the guy at the store told me to get in my little tank. I do have two PVC burrows at opposite ends of the tank-maybe this would ease conflict? <<I think they will be fine>> The other fish that I would like to get are either a blue or a citron clown goby (1") and a yellow watchman (2"). Would they be good tankmates with the Firefish? <<Either are fine>> One more question, the tank is at ground level (fully covered) and my cats have taken to sitting and watching the Firefish all day. She seems to watch them back and doesn't hide or anything, but could they be stressing her out? <<Have always had cats myself until late last year, these have never caused a problem once the fish get used to them being around. Nothing i would say to worry about>> Thank you again for everything! I hope you have a great weekend! Mandy <<Hope this helps Mandy, enjoy the rest of the weekend. A Nixon>>

Firefish addition & ... stkg. small SW Hi, I have been pouring over your site for a couple of months and it was invaluable in helping me set up my tank, thanks very much to your wonderful crew! <Welcome> Background on my tank: it is a BioCube 29; still using the bio balls and stock filtration, but with a skimmer on the way; 34 pounds of live rock and 20 pounds of live sand. Inhabitants are: 1 Coral Beauty, <Needs more room than this... by far> 1 Gold Head Sleeper Goby, 1 Red Spotted Scooter Blenny, 2 True Percula Clownfish (tank bred), 1 bubble tip anemone, <Dangerous here...> 1 Firefish Goby, 1 Scarlet Skunk Cleaner Shrimp, and various hermits and snails. I set up my tank and allowed it to cycle for two weeks, then began adding the cleanup crew of hermit crabs and snails. Noted large numbers of copepods and feather dusters coming out of the rock. After 3 weeks I began adding the current inhabitants. My question involves my Firefish. Since he has been added, he has been hiding in the back of the tank behind the live rock, <... this species needs a minimum (of the stated on WWM...) two square feet of bottom... to itself... and is not a solitary...> only venturing out rarely (only seen him come out into the front of the tank once in 3 weeks) or slightly more frequently hovering over the rock. I would like to introduce another Firefish in order to maybe coax it to come out more often. Now I have read you should only keep 1 male per tank. I am not sure whether I have a male or female, how can I tell? <Mmm, not easy w/o the animals being "side by side"... best to have a group, let them sort themselves out... or buy as "pairs"> I tried searching WetWebMedia and the Internet and all I have found is this, "It is hard to tell the difference between male and female but the length of their dorsal fin may be different.". Also, if I can determine if I have a male or female, as they were not introduced at the same time, will introduction of another Firefish at this time be hazardous? <... this system is too small for Nemateleotris, or Centropyge... had you read...> Oh and in case you are wondering, the scooter is doing fine, grazing all the time, and although I no longer see copepods running all over the tank, they are still present when I closely inspect my rock, and he has been taking some prepared foods. I have some Cyclop-eeze on order that I have seen others have had success in target feeding scooter blennies, just hope I can wean the scooter onto it, it will make me feel better. I was not aware when I got him how slow, methodical, and finicky eaters they are. Thanks much, Karl <Save up for a larger system; return the two fish... Bob Fenner>

Bioload and Firefish compatibility 02/27/2008 Greetings reef gods and goddess, <<No gods or goddesses here, just Andrew>> My question is regarding the possible addition of a Helfrich's Firefish. First of all, will this fish be accepted by a purple Firefish who has been established in the tank for about 5 months? My LFS says they are schooling fish and enjoy one another's company...I never take vendor's advice at face value. <<I would not add this to a tank which already houses a purple Firefish, due to clash. Helfrich does usually tend to ignore other tank inhabitants, however, I would see this fish being a little aggressive to others of its kind>> If it is OK to add this fish, my second question is in regards to its effect on my bioload. I currently have a 29 gallon system with 2 Percs, a yellow watchman and a purple Firefish. Inverts consist of a collection of hardy soft corals and a few LPS. I skim aggressively, have a small refugium with Chaeto and have red grape algae in the display to control for nutrients and trates. I habitually change 5 gallons twice a week. Would I be pushing the envelop with the addition of this Firefish? Thanks for your ongoing service to the aquatic community. <<You would not be pushing the bio-load by adding another small fish, but I think its wise not to choose this particular one for reasons stated above>> <<Thanks for the questions, I hope this helps. A Nixon>>

Re: Coral eater  2/4/08 Hi, I have Halichoeres chrysus. Could the fire fish be eating my corals? <Microdesmids rarely chew on Cnidarians> Also can the hermit crabs be a predator? <Oh yes. B> Regards, PraKash

Firefish... Mixing species  9/5/07 Good Afternoon! <Mmm, good not exactly sure what you call 3 a.m. but for me it would be good evening, Mich here.> I would like to buy a Helfrichi Firefish and a purple Firefish. Will the two get along? <At $150 for Helfrich's Firefish, I would never take the chance.> I read, on the Internet, that Firefish cannot coexist with members of the same species. <Not often.> But what about members of the same family? My tank is 75 gallons. <I would not do this, your tank is not that large and perhaps you haven't priced the very beautiful but exceedingly expensive Nemateleotris helfrichi. I think a little shopping may change your mind. Cheers, Mich>

More scissortail Dartfish questions... sys., comp., beh.   8/9/07 Thanks for your patience with me and my Dartfish questions. To recap quickly, I had a pair of scissortail Dartfish, but my tank wasn't well enough covered, and one of them jumped out of the tank and died. The other one became very stressed after that and hid under a rock constantly. <A quite common scenario> After sealing our tank cover better, we went back to our LFS and bought three more Scissortails. When we put them in the tank, our original Dartfish immediately came out and started swimming with them, and now is eating and swimming normally again. So I guess it really was depression/stress/loneliness that was getting to him! However, now we have a new problem. One of the new Dartfish seems to have disappeared. The last two nights, only three have come out for feedings. We searched all around the carpet and there have been no more escapees, so I wonder if it died inside their burrow or something like that. <Possible> Soon after that fish disappeared, A) one of the other new Dartfish began hiding in the burrow most of the time, and B) we noticed our fairy wrasse begin to bother the Dartfish, scaring them back into their cave frequently. The wrasse never bothered our original pair of Dartfish, who had already been living in the tank for a few weeks when we added him, and in fact the surviving Dartfish from that pair (who I can recognize because his fin is darker than the others) is not afraid of the wrasse and swims around him with no compunctions. However, the new Dartfish go whizzing into their cave whenever he comes near them. I'm concerned that the third one, who is most skittish, may not be getting enough to eat (he does eat at every meal, but only a little.) I also wonder whether this may have been what caused the death of the missing fish (though I should say that none of the new Dartfish were this skittish until one of them disappeared, so their newfound fearfulness may be the effect of the missing dartfish's death rather than the cause.) <A possible contributing cause> So I guess my questions are these: 1) Is there anything we can do to help the skittish scissortail survive? <More space, less Cirrhilabrus...> It's a 55-gallon tank with lots of live rock, holes, sand, different hiding places, etcetera, but the fairy wrasse does seem to preferentially go over and swim right around the entrance to their nest. One of the new fish feels comfortable swimming around the tank as long as the original Dartfish is out, wrasse or no wrasse, but the other one has been completely panicky since the disappearance of the fourth guy. 2) Unless the missing fish miraculously turns up alive, we're back down to three Dartfish. Is that an OK number? The LFS said it ought to be fine when I called them. <Is fine> 3) This is the question I feel embarrassed about asking, but I can't help thinking about it; I've read the FAQ's and online information and entries in our fish books and everything says that fairy wrasses are NOT fish-eaters like some other kinds of wrasses, but is there any chance he could have eaten the missing Dartfish? <Mmm, perhaps if it were dead, the Cirrhilabrus very hungry... It could well have harassed the Microdesmid/s in this small volume, particularly if it is/was solitary... Fairy/Velvet Wrasses are very social animals...> He never *looks* like he's hunting them-- I mean he never lunges at them or anything-- and he's only about three inches long, but still, the fact that they're acting so afraid of him all of a sudden makes me wonder. The Dartfish are smaller than the wrasse is, maybe two inches long each. <Just territoriality and lack of other social interaction> Our water quality's been perfect, if that makes any difference. We've been feeding them frozen Mysid shrimp and the Spirulina-enriched brine shrimp. Is it possible we might be underfeeding them? <Mmm, doubtful. Do they appear thin?> Thanks for any insights you might have! Laura <Welcome. Bob Fenner> Re: Pink watchman goby and ich, now Firefish comp.  -- 07/26/07 Hi Bob, Thank you for your kind words. I've had a bit of an emergency and am perplexed as to what to do. I woke up this morning and my Firefish has a wound (appears white) at the base of the anal fin and her fins are frayed. At night she goes into a hole in the live rock and I know there are things living in there but is there anything that could have attacked her?.. or could it have been the goby or Mithrax crabs? <Easily> Actually the real question is should I put her in a quarantine tank until that wound heals? <Better to move, remove the probable cause/s> She is swimming, eating and breathing just as normal as she was yesterday. Thanks.. Jennifer <Do keep a sharp watch... doesn't take much for further damage... BobF>

Re: Pink watchman goby and ich -- 07/26/07 Ok, thanks Bob. I have a feeling it was the goby...he has a guilty look. I'll continue keeping a sharp eye on the Firefish...I've had her the longest so I'm rather partial to her. Thanks for your help....again! Jennifer <Real good. BobF> Suitable Tank Mates For Nemateleotris decora (Purple Firefish) -- 06/04/07 Hi WWM, <<Hello Mike>> I have a 37-gallon tank with a 2.5-inch sand bed for my Purple Firefish. <<A wonderful little fish>> I was looking to get some passive fish to get along with him. <<Ah yes, very important...these fishes are often lost merely due to placement in systems with boisterous tankmates...really do best in 'calm' environments in my opinion>> I was considering a Banner Cardinal and possibly a Fairy or Flasher Wrasse. <<I am assuming the Banner Cardinal is Pterapogon kauderni, also known as the Banggai Cardinal. The Cardinal would be fine, even a pair if you can find one. Sphaeramia nematoptera is another (maybe better) choice as well...and also more likely to 'play nice' with their own kind in my experience than is P. kauderni. As for the Wrasses, I feel this tank is too small>> I was also considering a second Firefish instead of the Wrasse, but wasn't sure if my tank was large enough. <<A pair of Cardinals and a pair of Firefish would be fine...the problems come in the pairings. Nemateleotris decora do not do well with conspecifics usually (this is a bit less of a problem with Nemateleotris magnifica)...unless you are lucky enough to find them as a pair already or have a very large system to place them in. In a tank the size of yours, I think adding another N. decora with one already established will prove quite problematic>> My Firefish does have lots of places to hide, lots of caves and such he hides in. <<Is important for this species>> He is doing well, he eats and greets me when I enter the room. Also my tank is going to be reef soon. <<No tangs please...!>> As soon as I get my parameters to desired levels. Don't worry they aren't bad, just need to lower Nitrates from 15 to about 0 and raise my magnesium 100 ppm or so. <<Mmm...actually, nitrate readings of about 3ppm can be beneficial to reef systems>> Thanks, Mike <<Happy to assist. EricR>>  

Re: Suitable Tank Mates For Nemateleotris decora (Purple Firefish) -- 06/06/07 Thanks for the response, <<Quite welcome>> Since adding a 2nd Firefish could be risky at this point, I would just be concerned with him having company. <<Then perhaps just the pair of Cardinals>> I will greatly look into the Cardinals, and do you think they would "socialize" with the Firefish to keep him happy? <<As in 'school' together...no...but each will be aware of the others presence/actions...all should be fine>> Would a Nemateleotris magnifica do well with him? <<Would likely be as risky as adding another N. decora>> I wasn't sure if you could mix the species or not, I thought I read on your site somewhere that it could be done, but wasn't sure if it was at the same time or some other situation. <<There are always exceptions/differences in situations. My own experience and opinion is this type mix in a 37g tank; more often than not, will result in the demise of the new addition>> I also thought I would overstock my tank with 2 Firefish and 2 cardinals. <<Would put you at your limit perhaps, but is doable with the smaller species of Cardinals...in my opinion>> Lastly, my purple Firefish is doing well. He tends to spend his time near his "dart hole" and comes out when lights come on, time to eat, or I walk by. <<Excellent>> Great fish! <<They are indeed>> From, Mike <<Regards, EricR>>  

Sudden N. decora death   3/7/07 Dear WWM Crew, <Hello Brandon today.> As always, thanks for all of your help along the way. <Thank you for your kind words.> We have a 72G reef tank with about 80 lbs. of LR.  Our water parameters are (Temp=77deg F, SG=1.025, pH=8.3, Ca=380ppm, Mg=1290ppm, dKH=6.75, Ammonia & Nitrite=0ppm, NO3= 5ppm).  The tank was set up and cycled last May.    <Cool.> For about the last six months our live stock has consisted of a pair of clowns (A. ocellaris), a purple Firefish (N. decora), a fat mandarin (S. splendidus), and a school of 9 Chromis viridis.  Various corals, a tube worm (Protula magnifica) 2 turbo snails and some blue legged hermit crabs. In addition to this we have 3 peppermint shrimp (L. wurdemanni) & one big, beautiful fire shrimp (L. debelius). On February 17th, 2007 we added another fire shrimp (L. debelius) and a pair of cleaner shrimp (L. amboinensis).  Everything seemed great for the last two weeks or so, until this last Sunday morning (the 4th). Our purple Firefish, which had looked fine & had eaten heartily Saturday night, showed up Sunday morning looking very roughed up.  There were two whitish abrasions on its left side, its left swimming fin, dorsal and ventral fins as well as its tail were damaged. <Sounds like fighting.  Or a close escape.>  It died Sunday night and was subsequently eaten by the fire shrimp. <Mmmm.  Sorry to hear that.> This fish had an excellent home inside a small cave (see attached photos) that it had lived in since last August. What could have happened?!?!  None of our research, including your excellent site, indicated that any of our shrimp types attacked and ate healthy fish. Could a disease have done this?  All of the rest of the fish look fine and are eating well and the corals look great. <It is possible that it and the clowns could have been fighting.  More likely than that you could have a predatory creature in your tank that you have not seen.  Try feeding the tank after dark, and watching with a flashlight to see what comes out.  This is what I would do.  I have not heard of a disease that manifests that quickly.  There is even a possibility that the shrimp that you have are at fault.  There is no such thing as a truly safe shrimp.> We are broken hearted over this loss and need to know, if possible, what killed this sweet little fish (our favorite, actually).  Any help would be greatly appreciated. <To be honest, I am not 100% sure.  Bob?  Mich?  Any ideas?> <<Mmm, I do think the Debelius' shrimp was involved here. RMF>> Thanks so much!
<You are welcome, Brandon>
Jan & Ellen

Re: Sudden N. decora death   3/8/07 Dear WWM Crew/Brandon, <Hello Brandon again.> Thanks so much for your reply. <You are welcome.  I do my best.> As a follow up, the only creatures that we have observed of any size that have "hitchhiked" into our tank are some bristle worms.  <I was thinking that if you fed the tank after dark, you might see a Mantis Shrimp.  Did you try this?>  Some of these are quite large, about 2 inches in length and only seem to be in the same area that our Firefish inhabited.  <Even at this size, I would not worry about them.  They will generally only go after dead creatures.>  We have not added any LR since setting up the tank in May 2006 so the killer, if a hitchhiker, has been in the tank all along. Could these worms have had anything to do with this? <Please see above.> Right now, all suspicion is falling on the new fire shrimp which was seen feasting the Firefish. <It is a possibility.  If you will check out http://www.wetwebmedia.com/clrshrpcompfaqs.htm.  You will see where Bob has posted that he believes that the L. debelius was at fault here.> We are afraid to add anything to our tank with an unidentified killer on the loose! <I would look to the L. debelius.  You could move him to another tank, take him back to the store, or not keep small fishes with him.> Thanks again for all of your help, <Any time,  Brandon.>
Jan & Ellen

Firefish attacked by Black Perc. 1/26/07 Hey guys, how are you today? <I am well, considering the 10-degree day outside. Thanks.> I purchased a Firefish about 3 days ago and placed him in my 50 gallon tank with 2 Perc's, a Royal Gramma, and a Hot-pink Pseudochromis. <Two issues here, Tom: 1) No QT. New introductions should be QT'd for 3-6 wks for inspection, etc. 2) This ultra docile fish should not have been added lastly to this (or any) setup. I am not at all surprised by this outcome, given his tankmates.> He should have been the last <First, actually...> piece to the puzzle, but of course when you're dealing with fish you're dealing with personalities no matter what's said to be compatible. He seems to have a problem being welcomed to what was a "Peaceful Community". My smaller Orange Perc. seems not to mind he's there, and neither does any of the other fish either, but my larger Black Perc. hates! him. He <"She" is probable...> nips at him every time he comes out, whether it be for food, a swim, whatever. I understand the Black Perc. may be territorial and is known for being aggressive (damn damsels), but geez! Is he going to chill? <Probably not.> I'm afraid for the Firefish and if I could get him out I would but he's too fast. <You can see where planning in advance would've been prudent here?> My Black Perc's easier to catch if I tried but he was the first fish in there. Not even his Orange friend was welcomed like this, in fact he LOVES him. They are a true pair no matter what color each is, inseparable. I want my Firefish to be free from harm, not starving. Help! <I can recommend a few paths for you to follow here. Remove both clowns to a separate system for a while, as the Firefish gains confidence in his surroundings. Rearrange the decor while both clowns are removed, and after a few weeks, you could reintroduce the clowns to the 50gal. Another route would be to remove (permanently) the clown or Firefish. -GrahamT.>

Re: Firefish MIA   10/30/06 Well, I don't believe it, but here is a picture of my new Pink spotted watchman goby (Cryptocentrus leptocephalus) 4 inch with a Firefish in his mouth.  I don't know if this was after the Firefish had died but nevertheless I thought watchman goby don't' eat other fish. << The Firefish looks to be recently deceased, probably less than 24 hours when the picture was taken. I have found no accounts of Watchman Gobies taking fish this size as food items, but that doesn't mean it couldn't happen. More likely the Watchman is eating the remains of the dead Firefish. - Emerson >>

Firefish/Compatibility Questions 10/25/06 Hello Mr. Fenner <James today, for the lucky vacationing Mr. Fenner.> Hope you are doing great! <I am, and sure Bob is.> I have some questions. I have 2 small Domino Damsels (3/4 inch) 2 Blue Damsels (1 inch), 2 small Bannerfish (2 inch), 3 dancing shrimps and lots of live rock in my 80G tank. <You will soon curse yourself for buying the damsels.  Will turn into town bullies.> I just added my fish 2 days back. Before that there were some small feather dusters on my live rock but just after I added my fish they seem dead, eaten or not coming out of their cocoons. There were 1 or 2 small crabs on my live rock also which I saw crawling near the feather dusters in the night, maybe they ate it. Which do you think it was? My fish ate them or the crabs? <I'd vote for the Bannerfish in doing the deed, although they may have had help from the crabs.> These crabs look like small human brains and they are brown. Do you know which kind they are? And are they a negative aspect for the tank? Most, if not all shell less crabs are not good candidates for your tank.  I'd remove, keep in a separate tank if you wish to keep.> Also I need to know whether I can add 2 purple Firefish (decora) -- which I heard are pretty aggressive in the Dartfish family <Where did you hear that?  Untrue.> with the above livestock. <You already have non-compatible fish by mixing the Bannerfish with the damsels.  Firefish would not fare well with the damsels present, and the Bannerfish more than likely will not do much better.  A better choice would be the Firefish and the Bannerfish with no damsels.> I know they get frightened and hide under the rocks a lot but do you think that this type will be compatible with the fish mentioned above? <Absolutely not.> Thanks in advance for any advice. <You're welcome.  James (Salty Dog)> Best regards, Rachel Compatibility - 10/13/06 Do you think two Nemateleotris magnifica and one Sphaeramia nematoptera can be kept together? <<Indeed...should not be a problem>> Thank you so much for your advice. <<Quite welcome, EricR>>

Firefish Aggression 10/2/06 Hi and tanks for all the great information! <Hi> I am a bit confused as to what is happening and hopefully you can help. <Will try> Some background first, I have a 90G tank with 20G sump and 5G refuge that has been established for 10+ months, 1" sand, 100+ lbs live rock, and corals.  I have had all my current livestock for 4+ months in the main tank as follow: 1 Mandarin, 1 algae blenny, 2 Firefish, 2 O. clowns, 1 cleaner shrimp, 2 peppermint shrimp, 1 emerald crab, and cleaning crew (100+ snails & crabs). <Sounds nice.> I bought both Firefish at the same time in a LFS as a pair and they were in the same tank.  They have always swum together and slept together until now. The day after I added a Hector's goby, I noticed one of the Firefish was not with the other swimming about as normal.  He was hiding in a new spot (not seen in before) and not coming out to swim.  That night they were not sleeping together, still in new spot.  The next day I noticed that it was the larger of the Firefish that was chasing the smaller until he would go hide in the new spot.  The hector seems to be hanging out at the bottom doing just fine, peaceful not bothering anyone.  Both Firefish were out at feeding and both were seen eating, but shortly after the smaller was chased again back to the new spot.  Do you have any idea what may be causing this aggression in the larger Firefish? <Aggression between Firefish is not uncommon, as they mature their behavior can change like this.  When the new fish was added a new pecking order was established, and the little guy ended up low man on the totem pole.> Should I wait a few days to see if it passes or remove ASAP?  The smaller one does not appear to be damaged at all. <As long as he is eating and no damage is being done I would give it a little time, see if it works itself out.> Thanks for your time, <Sure> Patrick <Chris>

Re: Firefish Aggression 10/15/06 Hi and thanks for the information, Here is an update... The picked on one is now coming out a lot more and is out most of the day now and is eating fine, BUT he has one large tear in his tail fin (noticed yesterday). I tried to catch one after a few days but they are way to fast and I don't want to take out all the rock just to catch him, but if it gets worse I will. <Good choice.>  They seem to keep to opposite ends of the tank now. <They have established their territories.> I think he tore him a new a$$ and they are now OK with their new territory?    <Probably, may see some more aggression in the future, but as long as both are eating and no major damage is done should be ok.> I think the addition of the goby is just a coincidence. <An X factor, disrupts the status quo.> Thanks again, Pat <Good to hear things are working themselves out.> <Chris>

I like microdesmids. Me too... Comp., Sel.   9/16/06 Hi,    <Hello there>   I have a 120 gallon tank which I would like to stock with microdesmids.  Particularly, I would like to keep 3 bar gobies, 2 red Firefish and 1 purple Firefish.  If that's too crazy, would 3 red and a purple be OK? <Mmm, possibly... these species are not found together in the wild...>   My tank is a 4x2x2 feet.  Would it be possible to aquascape the tank in such a way that the fish would have a reasonable possibility of peacefully coexisting? <How to put this...? If it were me/mine, I'd rather not impose  too-unnatural circumstance/s... to foster more natural behavior, less stressful>   Also, my perfect aquascaping would be a home for some zoos (with 4x96 W PC bulbs) and "other softies", but I am most interested in the fish.       I realize that so far my two questions are vague and specifics are needed, but since I am most interested in the aforementioned fish <More than one species is fishes... a pet peeve> as the most important part of my stocking plan.  I want Dartfish and while I want other fish too, Dartfish are my top priority.  I thought I would get input proceeding any further.  From searching your site, there is not a consensus on the stocking limit of these fish (ranging from 1 to 20 gallons to don't keep more than one in less than several hundred gallons).  The rest of my stocking strategy depends on your answer (or rather, how I respond to your advice, but be assured I wouldn't be asking if I wasn't willing to consider the answer).      Thanks      Nate Terry <The larger, more peaceful setting you can provide, the better for Microdesmids. Bob Fenner> Stocking a 55 9/5/06 Hello Crew: <Hi> I am in the process of restocking my 55 Gallon so that it is more appropriate for the residents.  I currently have 2 Perc. Clowns, 1 Royal Gramma, 1 Sixline Wrasse, and 1 Neon Goby.  I plan on getting a Flame Angel and Yellow Watchman Goby.  Would I be able to add a Firefish or two? My concern is that the Sixline and the Gramma will be a little to tough of tank mates.  Thank you for the advise. <I agree that the Gramma and wrasse will likely make life difficult on the Firefish.  I think if you leave out the Firefish you will have a comfortable bioload anyways.> <Chris>

Ptereleotris evides (black Dartfish)  immunity to Porcupine Poison?   7/16/06 Hi, <Hello there> the question I have is short, the reason is not. I will add the reason just in case I am on the wrong track. <Okay> Q. Having trawled around the Web & your as always excellent site I cannot confirm a suspicion, If the Black Dartfish (Ptereleotris evides) is known at all, to be resilient or immune to the Porcupine Puffer's toxin (released when stressed)? <Mmm, don't know> The reason for this question is that this morning I woke up to a tank of dead fish. The porcupine puffer was stressed but the two black Dartfish were fine. <Interesting... could be that they were the smallest... had/have the largest percentage gill surface area... more sedentary/less need for dissolved oxygen...> Tank: 90ukgal - 3 year old Filters Fluval 404 on spray bar, Fluval 304 & LAC 828 Vecton UV15 sterilizer Deltec MCE 600 (considering changing due to bearing noise problem) Lid houses 2 T5 lights & Marine blue Live rock, 3/4" to 1" sand, no corals RO changes Water quality spot on bar 1mg/l Phosphate (before water change) Fish established 1- 3 Years: 5" Pink tail Trigger - RIP Cleaner Wrasse - RIP 4.5" Blue Cheek Goby - RIP Two 4" Monos - RIP 4" Sailfin Tang - RIP 5" Birdnose Wrasse in final transition from female to male - RIP 5" Porcupine Puffer - now RIP Two 3.5"-4" Black Dartfish - fine (now, just incase, in other marine tank) Circumstance: On light feeding last night I noticed two light rocks out of position (dislodged) - so I repositioned. This morning I awoke & found all but the puffer & Dartfish dead (Pinktail was floating). At 80 degrees F & a topped up water level to the spray bar, <He's likely the one who was "bothering" the puffer> I initially wondered about oxygen depravation. <Me too> After a couple of phone calls once the dead were removed, I setup a hasty water change & did 30% approximately 40 min.s later. <Good move> As my one available QT tank was set for freshwater due to an ongoing ammonia problem in my Discus tank (due to a piece of wood in the inlet tube of my Eheim Wet/Dry making it run low - still awaiting it to cycle as do daily water changes) & the other QT tank is rearing toadfish; I shot down to my LFS and got some more carbon media. When I left the Porcupine was still stressed, when I got back he was slightly puffed up & RIP. On removal he was coated in slime (I assume another toxin release) & the same rocks were dislodged again. <Strange about the rocks...> So far I assume a toxin release (some of the RIP fish were agape - & fairly quick after feeding last night as two out of 4 defrosted frozen shrimp were still left; a big oddity), but to my amazement the Dartfish were fine/happy??? Taking no chances (I do anything to help my fish) I transferred them into my reef tank (open topped with 6" rise above the water, I will be watching for jumps till I can be sure of the other tank). <Good> I am told the carbon should clear up the toxin now, but still wonder about the tough little Black Dartfish. <Me too> Any input would be greatly welcome/appreciated. Ed <It may well be that microdesmids are more "immune" to tetradotoxins... or perhaps it was/is something to do with gaseous exchange at play here. If it were me, mine, I would likely change about all the water out of the contaminated system... for general purposes. Bob Fenner> Re: Ptereleotris evides (black Dartfish)  immunity to Porcupine Poison?  7/18/06 Hi Bob Fenner, <Ed> Cheers for the reply. Water is being changed + new carbon (again) & new PolyFilter (told it would be a good idea - certainly no harm). <Agreed. Bob Fenner> Thanks    Ed 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  

Re:  Compatibility...Fin Nipping Re: Firefish & Anemone  6/12/06 Dear Mr. Bob Fenner / James (Salty Dog) <Rachel> Thanks for your reply. I really appreciate it. <You're welcome.> Ok the problem is this. I can never catch the 2 Firefish I bought with all the live rock work I have in my tank but I do see them hiding in it. <This is the problem when no research is done on the livestock you wish to purchase.> Therefore I only can remove the big fish from my tank. From the Clarkii Clown, Hippo Tang, Banner fish and the Klunzinger's Wrasse what are the species I should remove to make a comfortable environment for the Firefish. <I would start with the clown and the wrasse and see if that doesn't improve things.> Also I have an 80G tank so if I want to place a Bulb Anemone (Entacmaea quadricolor) in the tank what is the recommended watt per gallon. <I presume you mean lighting.  Would like to know the depth of the tank first.  I'm thinking it is a rather deep tank.> Also when you quarantine an Anemone do you need a sand bed or liverock and a clown fish because the LFS wants me to buy all of them together. <I can see buying the liverock if the anemone is anchored on it, but not sand and the clownfish.  Does the guy go by Capone or Bugsy?  Nothing is really needed in the QT for an anemone beside the rock he is anchored on and proper lighting with good water movement.  Do change 10% of the water on weekly basis.> Thanks, best regards, <You're welcome.  James (Salty Dog)> Rachel

Re:  Compatibility...Fin Nipping Re: Firefish & Anemone  6/12/06 Dear James (Salty Dog) <Rachel> I did research on the Firefish before buying it but the reason was my LFS guys motivated/provoked me so much and they swore that the Firefish would be fine with my fish in the tank. I know now that I shouldn't have trusted them for anything. <Believe me, Firefish do not generally do well with aggressive eating fish.  They won't get enough food and are easily intimidated and will constantly retreat into the rockwork. In nature, a little different story as they form groups with each having his own 'bolt hole' so to speak, to retreat to when threatened.  They hover above their shelter, feeding on passing planktonic food. You cannot duplicate this in a closed system without crashing the tank.> Thanks for the advice. My tank is about 24 inches deep, 43 inches long and 18 inches wide. So what do you recommend for the lighting? Do you think the bulb anemone is a good anemone to start off with or is carpet anemone (electric green) better? <The Bulb Anemone is one of the easier ones to keep, but no anemone is easy to keep for any length of time.  Forget the Carpet Anemones, your tank isn't large enough and intense lighting is required.  The Bulb Anemone will require about five watts of light per gallon.> So if the anemone is not anchored on to a live rock can I just put it in a tank alone without a sand bed or live rock and keep it just on the glass floor of the tank for two weeks with good water movement and lighting. <Problem here is that it will be difficult to remove the anemone from the glass, especially if you have little experience with them.  If the anemone is going into its own tank, quarantining will not be necessary, just do not add any fish for three weeks, and only fish that are anemone safe.> I think my LFS is ripping me off. <Buyer beware.> Thanks, best regards, <You're welcome.  James (Salty Dog)> Rachel Problem with my Purple Firefish... three Microdesmid species in a 28 gallon   6/2/06     I'm really, really hoping one of you guys can help me. Over the past few days my Purple Firefish has come down with a malady I've never seen before. First, a bit about my tank. I'm running a 28 gal <Dangerously small for microdesmids...> bow front with roughly 32 lbs of Fiji live rock, a Prism Protein skimmer, an Emperor 280 hang on filter and a small power head. For invertebrates I have a Coral Banded Shrimp, a half dozen Turbo Snails, a dozen Blue Legged Hermits, 2 Emerald Crabs, a Fire Shrimp, a sand sifting star <This animal is misplaced here... too little room to sustain it w/o depleting your sand bed> and a ton of feather dusters that have grown off the rocks. For corals I have a small piece of rock with Green Polyps, about 8 or so Hairy Mushrooms (they've split a number of times) and more Pulsing Xenia than I know what to do with. For fish I have my Purple Firefish, a normal Firefish, a Zebra Dart Goby <These are not compatible...> and a breeding pair of Banggai Cardinals. I feed them all a mix of Spirulina Enriched Brine, Mysis Shrimp and Omega 3 Enriched Brine which I soak in Kent Marine Zoe and Garlic Xtreme. Besides all that I add Liquid Calcium daily, Strontium & Molybdenum twice a week and Iron and Iodine once a week.     With all that said here's my problem... A few days ago I noticed that my Firefishes gills seemed a little swollen compared to normal but he was still behaving normally (eating well and hanging out in the front of the tank like always). I did a small water change on the tank and figured he might be able to get over it on his own with some better quality water. He hasn't. Instead his gills now puff out a great deal, though only on his left side, and today he stopped eating. Underneath his jaw also looks puffed out, again only on his left side. When I look at him through the side of the tank it almost looks like there's an open sore on the back of his gills but I can't be certain. All in all it looks to me like he has a growth inside his gills and towards the bottom of his jaw. He's still acting perfectly normal, except that he'll approach food but not eat it, so I'm hoping it's not too late for him. I should probably mention that he's been in the tank for a few months and I don't think there's any way I'll be able to get him out of there because of how quickly he can make it to his bolt hole.     If you have any ideas or any recommendations that might help me I would be eternally in your debt. It'd be a shame to lose this fish because he's been an awesome addition to my tank thus far. Thanks in advance for any help you might be able to give me. Regards, Dan <Dan, what you and your fishes need is actually a much larger system. Impossible to trace the etiology of the ones illness here. It may be as you suggest that there is some nutritional or parasitic component... treatment though? Do you have a means of separating the one fish? Bob Fenner> Firefish Compatibility...Conspecifics and Otherwise - 05/13/06 Hi, <<Howdy>> I currently have 2 Firefish (Nemateleotris magnifica) and have had them for 2 weeks.  The first week was fine but recently I have seen 1 of them has become increasingly dominant and chases the other whenever it sees it. <<This is not atypical behavior>> What can I do in a situation like this? <<Remove one of the fish and return it to the store>> Whilst reading through your site I read that they prefer to be kept in groups of 3, could I take out these ones and buy another one and put all three in a quarantine tank for a while then reintroduce them all at once into the main tank? <<This "may" work...but I'm skeptical.  I hear/read to the contrary all the time, but in more than 30 years experience with this fish, I have never found them to be particularly "sociable" when it comes to conspecifics...even in large (100g+) displays.  A group may "appear" to get along for a while, but usually the weakest individual is harassed/slowly starving to death...and upon its demise the next weakest starts to decline...and the next...and the next...until only one is left.>> My quarantine tank is 30l and my main tank is a Aqua-Medic Percula 90 (about 290l) <<It's not so much about tank size with these small fish>> I was thinking of adding a Sixline wrasse to my tank eventually and was wondering if this would be compatible with the Firefish (also have 2 common clowns)? <<Mmm, I don't think the clowns or this wrasse are very good tank mates for the Firefish.  These really are shy (even skittish) little fish best kept with peaceful tank mates...which the clowns and Sixline are not.  Regards, EricR>> Compatibility/Marine   2/26/06 Hi Crew, <Hi Sam.> There seem to be many questions about compatibility and most of us, myself included, ignore your advice. You can see it in the question where they say 'and they all get along fine'. I have a 10 gallon with a Firefish, neon goby and clown goby and wanted to add a royal Gramma. I was told it would be overcrowding and the Gramma may be to aggressive in such a small tank. But I wanted the color so I bought a baby Gramma and all was fine for 9 months with the Gramma and Firefish staying near each other and chasing after the same food in the water column. Sometimes the Gramma lost his cool when the Firefish beat him to some food and he opened his mouth wide at the Firefish. The Firefish would either turn his tail towards the Gramma or would scoot away. I was sure I had a compatible group. Then all of a sudden the Firefish did not show up for feeding. After a few days I found him hiding and he was pretty shredded up. So to all who ask your advice I say- listen to the experts-unless you are willing to sacrifice a pretty animal just so you can have it your way for a while. <Well said.  James (Salty Dog)>

Pistol shrimp and Firefish   1/19/06 Hello crew, I recently 'bumped into' the topic of mantis and pistol shrimps while  looking for other info on the site.  I have a 75 gallon  FOWLR.  1- 3" Naso Tang, 1- 3" Coral Beauty Angel and 1-Firefish, and  1-Emerald Crab with about 6 small hermit crabs.  I placed my first  well-cured live rock into the display tank about 3 months ago.  A 14# piece  completely encrusted with coralline and very craggy and porous.   I  lost a coral banded shrimp and probably 2 or 3 small hermits but no fish over  the past 2 months or so.  I have never seen any other creatures day or  night in my tank besides the ones I purchased.   I now know that the  loud clicking I have heard on and off is likely a pistol or mantis. Yesterday I  performed the club soda method with a baster and also just poured some over the  rock but I heard and saw nothing.  Since the Emerald crab and other fish  have been untouched and the clicking can be heard when tank lights are on that  maybe it is a pistol shrimp rather than a mantis (pretty unscientific but my  hunch after reading all these posts plus additional research).   My Firefish has a nice little cave where some base rock meets  the substrate. Would the Pistol shrimp's friendly  relationship towards some gobies extend to a Firefish and maybe he is  living in the cave with him? <Possible, but generally only associate/share with gobies as the goby does shake the tail and warn the shrimp of any impending danger.  I have this relationship going on in my tank and it is quite amusing.> Secondly, I would like to know if you  think I should continue to pursue this unseen/unidentified culprit before adding  more rock and fish and eventually convert to a reef sometime in the  future? <Mark, I'm thinking you have a pistol shrimp.  The mantis shrimp is audible only during a strike at prey whereas the pistol will click whenever threatened.  It is the incredible speed of the club like front leg that generates the sound. Super high speed video actually translated the speed to 75 feet per second along with the impact generating well over 100x their body weight.  To be sure you could set up a mantis trap and see what you catch.  James (Salty Dog)> Thanks for the help,<You're welcome> Mark Just Firefish Remaining and Them So-Called Nasty Worms... 12/05/05 Hi there, <Howdy, Ali here...> We recently purchased two Firefish gobies. <Bad move, that unfortunately many, many good willed hobbyist fall victim too.> Unfortunately we put them in a tank with a royal Dottyback who picked on one of them so badly that he didn't make it (we removed the Dottyback to our nano tank-by himself). Another lesson learned. <Firefish are very prone to being picked on by more aggressive fish, and in all honesty, the Dottybacks can be true terrors, especially for similarly shaped fish such as Firefish. Regardless of that fact, Firefish are not 'grouping' or 'schooling' fish. They do tend to group up as juveniles, however once they reach maturity (and even sometimes before so) they are highly aggressive and territorial fish towards other Firefish within the group. It is best to always purchase Firefish singly and never as a pair or group. Many vendors are now marketing 'mated pairs' of Firefish, however even these fish will turn on each other in relatively short time.> So we have one remaining Firefish, and my husband read somewhere that inverts will prey on them. Is this true? We have a couple of emerald crabs and many hermit crabs. We have also spotted a couple of bristleworms which I'm worried will harm it (is a six line wrasse a good solution for this?). Our tank is 26 gallons. What do you think? <Emerald crabs generally become overly aggressive towards any small fish and are not recommended for the docile reef aquarium. Bristleworms and small hermits shouldn't pose any real problems. I wouldn't be too overly concerned with the bristleworms due to the fact that most of the bristleworms found in the hobby today are harmless detritivores. Many years back when wild Atlantic live rock was available to hobbyist, the large and nasty 'Fireworms' would appear. However, now a days most live rock is either Pacific or aquacultured Atlantic and the 'bad' bristle worms aren't commonly associated with them.> Thanks in advance, Jen <No problem Jen and good luck! - Ali>

Microdesmid stocking 7/26/05 Hey Crew, I have one quick question... If I get for my 55G FOWLR two Nemateleotris decora (mated pair) and two Nemateleotris magnifica (mated pair), will they get along? thanks, I read that they may not tolerate others of their own species, but I didn't know if these two species are too closely related for them to live in harmony. Mike <In a system of only four square foot bottom space I would only house one species of Dartfish. Bob Fenner> One Firefish bullying two others 07/01/05 Hi all, <Kevin> We recently purchased 3 Firefish (after reading through all your articles and FAQs on the subject, of course).  Eventually, they are to be housed as the only fish in our 55g refugium.  Sadly, our quarantine tank is only 10g so we knew quarters were going to be tight for the first month.  One of the Firefish has quickly (within 2 days) assumed dominance over the tank and is bullying the other two, to the point that their fins are torn and they spend their time either hiding or fleeing from the bully. <Separate the bully, better still, return it. As they are older, most Firefish pair up...>   This sounds all-too-similar to the other stressful Firefish deaths detailed on your site and we'd like to avoid that outcome. Do you have any suggestions for how to deal with the situation?  If we have to remove a fish, should we remove the bully or the other two? <Either, but separate them ASAP> If we can somehow separate them during quarantine (by setting up another 10g tank?), <Or floating, caging up the bully> what are the odds that the same behavior would return once they were reunited in the 55g? <Too likely. Bob Fenner> Thanks in advance! Kevin and Susan Fiendish Firefish?  Unquarantined Clown - 09/03/2005 I have a well cycled (6 months) reef aquarium (keeping a Mandarin and Firefish with no problems- I <PLEASE, everyone - capitalize your "I"s!  We have to fix these errors, you know.  Takes forever.> breed Copepods for the Mandarin in separate culture tank). <Just be sure it's enough to keep the fish fat and happy....  Easier said than done.> The tank is only 30 gallons but I thought I should be able to keep about three fish. <Smallish, peaceful fish, yeah.> I just bought a false percula clownfish and it died 2 days later :(  The fish never seemed to be able to swim upright from the time I acclimated it and the fins deteriorated (or seemed to be tattered). I am wondering if the purple Firefish I had may have damaged it (when the lights were out as I never saw any aggression during the day)?   <Whaaaaat??  You didn't quarantine the clown?  I mean....  that's a sure invitation for disaster.> I know mandarins are not aggressive in this way, but before I get another clown, I would like to be sure the Firefish wasn't the cause. <It is very highly unlikely that the Firefish had anything whatsoever to do with this.  Just hope the clown didn't die of something communicable which has by now passed to the other fish in the tank.> Thanks for any info.  I think I just got a fish that had been moved too many times- the LFS store had just brought them in the day of my purchase. <Your next purchase really ought to be a small quarantine system.  It will save you money, time, grief, and work in the long run.> Darion <Wishing you well,  -Sabrina>

Fiendish Firefish?  Unquarantined Clown  - II - 09/07/2005 Thanks for the reply. <Of course.> While upset about the loss, I (capitalized) <YAY!  Thanks....  Really!> am unable to keep a quarantine tank at this time having only a 30g with fish stocked from the same store- all of the LFS's tanks run off of a single large filtration unit behind the display so I didn't think much of it. This was probably stupid as every new batch of fish they get could bring in a new disease (smacks self).   <Yup.  You got it.  And since ALL the tanks are run off a single filtration system, if ANY fish in the store has ich....  then potentially all have ich.  See?  Quarantine Is Good.> Frankly, a quarantine tank would be almost as large as my main- and I'm moving to my first house in about 1 and 1/2 months. <Ahh!  Congratulations!> I already have 4 tanks to move ranging from 60g down (all others are FW).   <Believe me....  I feel your pain....> I understand the reasons for a quarantine tank and will wait until I can set one up at the new place rather than just replace the fish. <Very, very good.  This will save you time, money, grief.... life....> Hopefully it was just stress rather than disease :/  I'll be watching my tank closely for a while.   <A good plan indeed.> Thank you for your time. I just wanted to be sure a Firefish is non-aggressive to clowns as some as the advice I have received from my LFS is suspect (sure a mandarin will be fine in a 30g with live rock- you don't even have to feed it). <The Firefish should be perfectly compatible.  I do hope your copepod farm is very productive!  Wishing you and your fish well (and thanks for the punctuation/capitalization!),  -Sabrina>

Firefish? Hello Bob, I was wondering if purple fire fish will fight with red Firefish? I have two red Firefish in my tank and was thinking of adding a purple Firefish or two? any compatibility problems? what about with Helfrich Firefish? thanks for the info! Ben Garbi <These three species of Dart Gobies (family Microdesmidae) can mix together peacefully given sufficient space... I would allow at the minimum, a good square foot of open (discounting the area covered by rock, other decor) of bottom per individual. However... it would be best to display one species per tank/system for behavioral and survival reasons. Bob Fenner>

Helfrich's  I'm thinking of adding a Nemateleotris Helfrichi (Helfrich's Firefish) and  was wondering if this is a hardy specimen, and if it would get along with  the other members of the Firefish family. I was also wondering what it's diet  consist of, and how long it may live in captivity. >> This Dartfish Goby (Microdesmidae) is about the same as its more popular, common shallower water conspecifics... best kept in a small group in a large system... generalized zooplanktivore... In propitious circumstances (rare) they live for a few years. Bob Fenner

Firefish I currently have a Firefish in quarantine. It has been there for a week and appears to be doing great (eating, reacting to my presence, etc.) I am wanting to add other fish to the quarantine tank but I know I can't do that until it's out.  <Not w/o starting the time clock back to zero...> Is it necessary to quarantine Firefish?  <Generally no... too timid, likely to suffer more from stress than it's worth... or jump out in the meanwhile...> Is it necessary to quarantine any fish that doesn't have scales?  <Yes> Do you think I could give it a freshwater bath and add it to the main tank without too much risk? I really am trying to be patient. . . . <Likely fine... best not kept singly... Bob Fenner> Keep up the good work Bob! David Dowless

Firefish and Lionfish... Oh, My! <Roger... Anthony Calfo in your service while Bob is away> Good evening Rob, to start I must tell you how impressed I am with the website, I've gotten lots of info from your site and it did stop me from getting a mandarin goby (thank goodness), and I work in a pet store so I share the info I find with customers who ask about certain species I have read up on here (salt water). Although we don't sell salt water fish but the store in town that does is always closed Sundays and so sometimes there customers ask us in desperation. Any how, I bought a beautiful 3" lion fish, I know it's not a dwarf but it doesn't look completely like any on your web site (I'm assuming due to it being a juvenile. But I digress, I have a pair of fire fish whom I have had for at least six months and they live under some slates of marble that are just wide enough for them, originally as protection from my coral banded shrimp who I'll now trade in for a prickly leather jacket (according to my research it should be a good tank mate for my lion). Any way, I've become rather attached to my fire fish and would like to know if you think that their cautious nature will be enough or if I should exchange them so that they have a better chance of survival. <under no circumstance could the Firefish survive in this tank... they are sure to be eaten. And with all due respect... the very nature of the question indicates your relatively new participation in the hobby. Kudos to you for taking the time to gather information first. Indeed, we must take the time to learn everyday. To the point... without deference to Bob out of posterity... I strongly suggest you buy and read The Conscientious Marine Aquarist. It is loaded with the very information you seek. Easily one of the best references on marine aquariology that you will find. And keep learning! Anthony>

Firefish and Lionfish... Reply! Thank you Anthony, for your quick reply, <quite welcome James> and I will do just as you suggested. As you guessed I am new to salt water. <a beautiful thing...we all start somewhere. Enjoy the magic of discovery> I've done fresh, tropical and brackish for the past 10+ years and decided a year ago this February to give salt a try. So far it's been a real challenge, many of the tricks you learn for the others aren't applicable. Any how, I'm always on the watch for books and I'll ask my boss to find that book for me. I must admit that I had a feeling the answer to my fire fish question would be no but I've always found it good to ask for a second opinion.  <absolutely...good instincts. Please don't hesitate to call again. If you aren't doing so already... peek in on our message board at WWF. And also look into the possibility of a local aquarium club/society. It's one of the best places to get honest information from people who aren't trying to sell you something. Best regards, Anthony> Thanks again, James 

- Adding some Firefish - <Hello, JasonC here...> Hi I have a 70 gallon reef tank with two ocellaris clown fish, I wanted to get a small group of Firefish, I was going to get like 3 of them would this be fine or would they fight with each other? <The chances are good that they will at least form a pair, with the third maybe accepted, may be tortured. These fish do live in groups in the wild so you're better off purchasing and placing them all at the same time. Keep an eye on them and remove the low man on the totem pole if things don't go well for him, otherwise... enjoy.> I do not want them to fight so would they be fine in a 70 gallon? <Yes, about 20g per individual.> I plan on getting a neon goby maybe a pair of Banggais and a yellow tang as my last addition? <Skip the tank, these grow as large as dinner plates and need much more room than you have currently.> Would the Firefish fit into the mix? <Yes, but don't over-crowd the tank - try to under stock and you will enjoy the tank much more.> Thanks a lot if you could help me out that would be great!! Thanks a lot! Sincerely, Nick <Cheers, J -- >

Fireworks? (Firefish  Population Dynamics...) Hey all, <Howzit? Scott F. with you today!> I've got a pair of purple Firefish (N. decora) in my 125 gallon.  Was doing some Gobioid research and saw the N. magnifica listed as a more communal fish.  Is it possible to successfully mix these pairs without much combat? <It's really hit-or-miss, in my experience. These fishes are often found in groups in the wild, but this dynamic does not always translate well in a captive situation. I've seen numerous attempts to keep several of these fishes in one aquarium, that ended up with one fish slowly killing all of the others, until there was only one left!> I've seen it suggested to keep as many as 1 per 20 gallons (on a WetWebMedia article, no doubt) and even I had to second guess that a bit. <As well you should...there are no guarantees with these fishes. You could try to find a mated pair, which is the most reliable way to keep more than one of these fishes together...> All in all, in the 125, I've got a Heniochus Bannerfish, a lawnmower blenny, two pajama cardinals, 2 maroon clownfish, and the two purple Firefish (N. decora).  I'd like to add a few of the N. magnifica if compatible. <Well, again- there is no guarantee here...If provided with a large tank, with plenty of hiding spaces, so that each fish can have it's own "territory", you may have your best chance of keeping more than one together.> My full stats are: 125 gallon, 150 lbs live rock and soft corals.  It's been up about a year.  The pair of Firefish have taken residence in the back corner of the tank under a rock (their 'bolt hole') Oh, and any way to determine sex besides size? (Because even just going on size can be misleading if you've got a pair of males and one is just dominant of the other).. <I'm not aware of any really reliable external sex differences...> Thank you very much, James C. Graham <You're quite welcome, James. I wish you luck on your endeavor! Regards, Scott F.>

Playing With Firefish Hi, I'd like to add Firefish to my 55-gallon tank. My questions are, how many could/should I add, and whether they would be compatible with the established inhabitants. I have two Ocellaris Clownfish and a Bicolor Blenny. No other fish yet, it's still a new system (7 weeks old). <Well, a good recommended stocking level for these guys would be one for every 20 gallons, which means that you could try 3 of them. However, when you take into account the dimensions of this tank, and the presence of other inhabitants, it might make more sense just to get one individual. However, if you have a lot of rockwork to provide "territories" for more than one fish, it might work. I would introduce all of the Firefish at one time, though. > I'd also like suggestions for additional future fish -- perhaps a macro-algae grazer appropriate for my tank size. Currently FOWLR, but I'd like to add soft corals and polyps within a few months. <Well, you could consider a specimen from one of the many species of smaller fairy wrasses, or, perhaps a Gramma. These are interesting, colorful fishes that stay reasonably small. Small gobies and blennies are nice, too...> I'm running a CPR BakPak Dual Pak (rated for 100 gal.) and a hang-on-tank canister for filtration and two Maxi-Jet 1200 powerheads for circulation. I have 50 lbs. live rock and a 4" sand bed. I'm hoping to add a refugium early next year. (Please point out any glaring problems you see with my setup.) <Nothing really wrong, but I do implore you to clean and/or replace any mechanical (filter pads) and chemical (i.e.; carbon) filtration media frequently> In case you need to know what invertebrates I have, they are: 2 Peppermint Shrimp, 1 Cleaner Shrimp, an Emerald Mithrax Crab, a Brittle Star, 30 hermit crabs, four Astrea snails, 12 Nassarius snail and a handful of Ceriths. <A nice mix to start with...> I'm new to marine aquarium keeping, and got really caught up in the invertebrates -- some of my favorite tank inhabitants -- and never quite got past planning for common clowns and the potential Firefish. <Interesting fishes, nonetheless!> The blenny was something of an impulse purchase -- although I knew he wouldn't be a problem with the clowns, I've since heard bicolor blennies sometimes badger Firefish, and as much as I love my blenny, I could certainly see this happening. <It is possible...> He's such a character. Also, will the clownfish pester the Firefish, since I'd be adding the Firefish after the clownfish (another mistake which I even knew about but made anyway)? <The clownfish could become a bit of a problem, once they get established.> Thank you for the site, I've learned lots more about this fascinating hobby since stumbling upon it (and have found that a lot of other newcomers have the same problems and panicky moments as I do). Sorry for the long e-mail. Thanks, Amy <A pleasure, Amy. Just keep thinking about compatibility and each fish's unique requirements (i.e.; territory, space, etc.), and you'll do fine. Good luck! Regards, Scott F>

Purple Firefish - Nemateleotris decora 4/19/04 Hi Guys, <howdy> I hope everything is well in wetwebworld, <were wacky and wonderful> Just a quick one. Had my CBS for about 6 months and I'm looking at purchasing a Purple Firefish. 50 Gallons with 20 lbs of live rocks. Should I rethink this stocking plan? <no worries... room here for a Firefish, to be sure> I read the faq on both species and one hobbyist were mentioning how his CBS killed the purple Firefish. Thank you again. Dan <CB shrimp are always unreliable/unpredictable. You simply never know how, if or when they will catch a little fishy. It is a chance, but likely small. Best regards, Anthony>

Firefish together Hi, <Hi Jonathan, MacL here with you this evening> I have a 29 gallon reef and am wondering if I can keep a purple and red Firefish in the tank without any problems. <I have kept them together with no problems other than that they tend to jump out of tanks>  In the 29, there is only a pair of ocellaris clowns.  Thanks!

Re: Purple and Red Firefish together in a 29 gallon? MacL, <Hi Jonathan!> Thanks for responding.  How big was your tank? <My very first saltwater tank was a 30 long and I loved it immensely.> I'm thinking since you are an expert, you must have a 150+ gallon beautiful tank =)<You are very kind calling me an expert.  Right now I have a 120 gallon reef, a forty cube, and a 180 tank running. All of these have sumps and refugiums.  But Jonathan, the size of the tank isn't what makes it beautiful, to me beauty is defined by the health and condition of what's inside the tank.>

Purple and Red Firefish MacL, <Hi again Jonathan> Which one of your many tanks have you successfully kept a purple and red Firefish? <I kept them in a 75 gallon tank together. BUT I had a large amount of live rock and lots of hiding places and lots of "escape" places for them.>  Wow, you have two 100+ gallon tanks.  Your electricity bill must be through the roof! <It is, lol> Firefish help Hi Was hoping you would be able to help me out with a small concern! On the weekend I purchased two Firefish which I identified from your site as being (Nemateleotris magnifica). I added them to my FOWL 55gallon tank which already includes three small Chromis  and one bicolor angel. The water parameters are fine. After adding the two Firefish, the bicolor angel started bullying them around a bit - but it wasn't anything too aggressive. When I woke up the next morning, there was only one Firefish and no sign of the other. He has now been missing for 36 hours with no sign of him anywhere. The other Firefish appears to be okay.. he's already started eating - although only when the food comes to him. So my questions are: 1) Do you think my Firefish is dead? <Yes>  I read somewhere that if they are shy, they can lock themselves into a bolt hole and not come out for a while.  <You would still get a glimpse of him during this time.> 2) If he is dead, was it because he was already doomed or do you think something in my tank was the culprit.  <Could be either/or. Firefish are best kept in a species tank or a tank with very non-aggressive fish.>  I find it hard to believe that the bicolor angel could have done that despite the harassment.  <Firefish are touchy to some degree. They are very timid and are not going to be very brave in going after food with a lot of other fish motion going on around them.> There are no traces of him to be seen anywhere. 3) I do have a crab that lives in my live rock who only comes out at night - could he have knocked him off?  <Don't know what kind of crab it is.>  And if he did, is it probable that that sort of event would have occurred on the very night that I added the fish?  <It's very possible.> 4) Is it okay to keep a Firefish on its own? I read that they need to be kept in at least pairs.  <They feel more comfortable in groups of three or more.> Although if it is the crab, then I assume the other wont be around for much longer.  <Let's hope it will.> Thanks for your help.. much appreciated. <You're welcome. Here is an article on Firefish you should read. http://www.wetwebmedia.com/ca/cav1i1/wormfishesArt/wormfishes.htm.  James (Salty Dog)>  

Firefish Help - II Wow. Thanks for the quick reply. I did read that article earlier today and found it very helpful. I am aiming to have a non aggressive tank. I never realized that the bicolor was aggressive. When I purchased the Firefish, they were actually being stored in the same tank as a bicolor, so I assumed that they would be compatible. Is there anything that I can do to help out the other Firefish.. I would hate to lose him too. But I guess not knowing the cause of the first death would make it hard to know what to do.  <I would see if your LFS would exchange it for something else.>  Over time, I was wanting to put in a Dottyback and a small tank bred percula as well.. do u think these fish are compatible?  <Should be OK, just don't get two Dottybacks, most if not all are aggressive toward each other. James (Salty Dog)> 

Stocking Level Wet Web Let me say first, sorry to bother you with another stocking question.  Currently I have a 30g tank, 2 powerheads (the exact gph escapes me right now), an AquaC remora and 2x96 PC lighting (1 10k lamp and 1 actinic 03 lamp). There's about 75lbs of LR in there with a 3" sandbed. Current livestock includes 3 smallish colonies of zoos and polyps, one bubble tip anemone, one unknown SPS frag (was given by a friend), 2 skunk cleaner shrimp, 3 peppermint shrimp, 2 smaller Percs and 1 Firefish. There used to be 2 Firefish, but one died this morning for unknown reasons. My first question is if it would be alright to introduce another Firefish (will the older one harass the new one to death?). <No, they generally do better in groups of three or more.><<James... this tank is way too small for these... a thirty with 75 pounds of live rock?! RMF>> Second question is what would be a good addition to this tank in your opinion. I was thinking along the lines of 2 neon gobies, or a royal Gramma and a yellow watchman, or possibly 3 green Chromis. Thanks in advance for any help/opinions.  <You could add two more Firefish or, the neon gobies and yellow watchman. The choice is yours, Mitch. James (Salty Dog)> 

Firefish Questions (2/5/05) Hi Aaron here,  <Hello. Steve Allen with you today.>  I recently purchased a Firefish goby and was wondering what are some suitable tank mates.  <That depends to a degree on what size of tank you're talking about. This fish is very timid and can easily be scared into permanent hiding to the point of starving. Avoid particularly aggressive fish such as Dottybacks and Damsels. A peaceful bottom-dwelling goby like the Yellow Watchman Goby would be fine. Royal Grammas, Percula or Ocellaris Clownfishes and Angels of the genus Centropyge usually work out, but can be aggressive. Peaceful wrasses (Flashers, for example) should be OK. Again, the choices depend on tank size.> Also, it kind of swims at angle. Almost vertical but it can level out and swim normal if it wants. Is this normal?  <They tend to hover at an angle and twitch their dorsal spin. This is normal.>  Lastly, would it be able to survive on a diet of brine shrimp and/or krill?  <Brine shrimp are the potato chips of the fish food world. Inadequate nutrition. Try a variety of frozen foods including krill, Mysis and others. There's a lot of great stuff out there. A small, high-quality pellet like Spectrum will be good as well.>  Thanks again for the help.  <You're welcome. I hope it helps.>

Fire Goby I have had a lot of ups and downs with my salt water aquarium of 30 gallons and in the process lost many fish due to inaccurate advice.  However, for the last 4 mos., I have maintained stability in my reef safe tank which is home to a beautiful but territorial maroon clown, fire goby, royal Gramma, and dragon goby.  I'd like to add one last fish to my aquarium.  I'm eager to add a Purple Fire Goby, but am not sure if it would fight with the Red Fire Goby already in my tank.  Any thoughts?  <Gobies tend to do best in groups of three or more of the same species.  If things are going good right now don't add another especially with the bully clown>  James

Considering Firefish I have a 60 gallon, LR/LS reef tank with 2 Chromis, a neon goby, pink Anemonefish, lawnmower blenny, mandarin goby (who, after 5 months, now has a flat tummy instead of a concave one!) <Good> , a fire shrimp, a sifting star, one snail and a Sailfin tang. I am considering purchasing a Scissortail goby-Ptereleotris evides and a fire goby-Nemateleotris magnifica. <Mmm, you'd be better off getting two of just one of these species> I know I should buy them at the same time, but I was concerned about how my other fish will react, and if the new ones will thrive. Most of the fish are pretty calm, other than spazzing and hiding, but the tang is one aggressive guy when it comes to food. He never nips or chases anyone, <Doesn't have to... the other fishes realize it's danger> but he eats pretty fast, and the food is gone pretty quickly. I have been reading that the Firefish may be slower eaters, and may starve if housed with faster eaters. Is this true, and will they learn to eat quickly? <Yes... if your mandarin is doing fine, so will these fish. Bob Fenner> Thanks, Rebecca Firefish Free-For-All (Keeping Several Firefish Together) 6/31/05 Hi all, <Hi there! Scott F. here today!> We recently purchased 3 Firefish (after reading through all your articles and FAQs on the subject, of course).  Eventually, they are to be housed as the only fish in our 55g refugium.  Sadly, our quarantine tank is only 10g so we knew quarters were going to be tight for the first month.  One of the Firefish has quickly (within 2 days) assumed dominance over the tank and is bullying the other two, to the point that their fins are torn and they spend their time either hiding or fleeing from the bully.  This sounds all-too-similar to the other stressful Firefish deaths detailed on your site and we'd like to avoid that outcome. <Yep- a common occurrence, unfortunately.> Do you have any suggestions for how to deal with the situation?  If we have to remove a fish, should we remove the bully or the other two? <Personally, I would be hesitant to keep a group of Firefish in all but the largest systems (several hundred gallons). Virtually every time I have tried (or people I know have tried) keeping multiple Firefish together, one inevitably becomes the "Alpha Fish" and succeeds in beating the others to death. I've seen people start with groups of 5 or more of these fish and end up with just one..> If we can somehow separate them during quarantine (by setting up another 10g tank?), what are the odds that the same behavior would return once they were reunited in the 55g? <Probably pretty good. And If you take away the bully, the next guy in line will step up and make life miserable for the other one...If you still want to try this, I'd get a couple of tank dividers and put them in the quarantine tank.> Thanks in advance! Kevin and Susan <My pleasure, guys. I don't want to be overly negative- it's just that myself and many hobbyists I know have had a notoriously difficult time keeping several of these fishes together. Maybe you'll have better luck! Regards, Scott F.>

Firefish Free-For All (Pt. 2) 6/31/05 Update: Just after I wrote this mail last night, we isolated the bully Firefish in a colander.  Sadly, the damage apparently has already been done for one of the other two, who later last night repeatedly threw himself against a pile of rock rubble until he showed bright red bruising all along one side. He then dug himself into the bottom of the rubble pile and drew his last breath :-(. <Sorry to hear that...> On the bright side, the other remaining, beaten-up fish is already showing signs of improvement.  Even if the trend continues though, we still have the original dilemma of what to do with these guys in the longer-term.  Any help would be appreciated. Thanks, Kevin and Susan <Well, I'd try to find separate homes for both fish. It's just a risky proposition keeping these guys together...Not much else I can suggest here. Good luck! Regards, Scott F.>  

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