Mantis issues   10/2/06
Hello,
Thank you for the wealth of information which your website offers, it has helped me immensely.  I've recently determined that my tank is inhabited  with one or more Mantis shrimp.  I get the familiar popping noises at night  which had baffled me for a while.
<Mmm, or could be Alpheids...>
I've lost 5 fish over the past two  months since I introduced some large pieces of live rock.  Two of the fish  I lost were of fairly good size.
<Oh...>
One was a Lawnmower Blenny of about 4  inches.  The other was a Fairy Wrasse of about 3.5 inches.  The Wrasse  had been found alive wedged in a crevice of some branching live rock.  I am  curious what you might think about this.
<Time to go Stomatopod hunting, removing>
It was quite a struggle to get  the Wrasse out of its position, and I ended up ripping it out with tweezers which  killed the poor thing.  
Could the Mantis have done this?
<Mmm... yes>
Or do fish  typically get stuck in rocks to where they must be ripped out?  
<Nope... no species-survival value in such behavior, eh?>
I also  wonder if my Blenny was killed by the Mantis or if it is possible/more likely to  have gotten stuck in a rock like the Wrasse.
<Highly unlikely>
I set up a trap using a small  plastic water container, cutting off the end and inverting it into the container  with a piece of mesh rubber banded around the mouth.  It's been a few days  with two of these traps baited with krill and still no luck, although I think I  heard a Mantis thumping on the plastic.  Any advice/help is greatly  appreciated.
Sincerely,
Chris
<Time to use the all-plastic re-labeled mouse-traps in my estimation. Bob Fenner>

Mantis Shrimp Hitchhiker...What To Do? - 07/23/06
Greetings Crew!
<<Phil>>
Well, it appears I might have a mantis shrimp lurking in my tank, which is approaching a year old.
<<Neat critters>>
I have had a number of hermit crabs mysteriously turn up eviscerated over the last 4 or 5 months.
<<I see>>
Originally I though it might be the olive snail burrowing through my substrate, but even after I returned him, the carnage continued.  On a couple of occasions back then, I though I heard the notorious clicking at night, but it was not frequent and seemed to disappear for a number of months.  Within the last week, I've heard it again after dark on several occasions and today I think I might have located the rascal.  I noticed something spewing gravel out of a small lair, and eventually it even showed a part of its body.
<<Making itself right at home, eh?>>
It was tan colored with darker stripes traversing its body.  However I only saw what I believe was the forward part of its body; it appeared to be somewhere between 3/16 and 1/4 inch wide from what I could tell.
<<Relatively small species then...likely of little concern, other than to your snails/hermits, etc.>>
If it is indeed a mantis, what would be the full length of his body if his carapace was 1/4" wide?
<<Hmm only guessing here, but I'd say 1.5" or less>>
I presume my hermits and snails will be in peril while he remains in the tank.
<<So it would already appear, yes>>
I'm guessing my fish (maroon clown, blue cheek goby, coral beauty, Foxface, bi-color blenny, 2 damsels) are relatively safe, however I am wondering whether he may develop an appetite for my new T. Crocea?
<<I don't think this is likely...especially if you manage to keep it fed with the occasional snail/hermit>>
I am somewhat of the philosophy to not intervene too much in what happens in my tank, assuming I am providing a somewhat stable, quasi-healthy environment for my charges.
<<Not to mention the behavior/antics of the mantis shrimp are in themselves interesting/to be enjoyed>>
However, I would definitely draw the line at the loss of my $80 clam.  What would be your opinion re the risks of leaving this hitchhiker versus removing him, and if I were to remove him, what is the method with the best chance of success.
<<I think the risks of leaving things be is small.  If you decide to remove, a baited trap (some are commercially available) or locating/removing the rock called "home", with a subsequent freshwater dip to drive the mantis out of hiding>>
And if I remove him, would it be unethical to 'terminate with extreme prejudice'?  I don't really have the luxury of setting up a species tank for him.
<<Why not trade to your LFS?  Someone would surely give it a home>>
Regards, Phil
<<Cheers, EricR>>

Peppermint shrimp and porcelain crabs... and Mantis and Clowns  7/18/06
Hi..
<Hello there>
I have a 55 gallon display tank that is being left fallow while my fish reside in a QT tank. I am well aware of the dangers that mantis shrimps
pose, and I know that one lived in my tank because I often saw him and he killed my coral banded shrimps. Now, I have not seen the mantis shrimp for
over a month and I no longer hear the clicking noises they make.
<... may be nothing to "click" about (live food items) present>
As an extra precaution I added some feeder ghost shrimps into my tank and they show no signs of being attacked.
<Oh! Good move>
Is it safe now to add 2 peppermint shrimps? My tank has plenty of live rock and hiding places.
<Only trying can/will tell>
Also, I had an anemone crab that was kicked out of the anemone by my pair of very aggressive tomato clowns. He lost about 6 of his legs and disappeared.
<Yikes, hopefully the legs will regenerate in a molt or three...>
Now that my tank is devoid of fish, I was thinking of adding a pair of porcelain crabs. If I let them live in the anemone for 3 weeks before I put
the pair of clowns back in, will they co exist within the same large anemone?
<Again, only experience can tell...>
Or should I get another anemone so they have one each?
<If this system is "large enough" this might work... It is not altogether improbable that the Clowns will "hog" all anemones...>
Thanks for
your help.
A
<Welcome. Bob Fenner>

Mantis Tactics Refined... and sponges   5/26/06
Greetings Crew:
<B in B>
On WWM there are many FAQs on how to rid a tank of a mantis shrimp.  I am thankful for that.  I have removed one using a new technique, and will be happy to send to you the details should you desire.
<Please do>
Meanwhile, I have two others that have evaded capture for 8 months now due to the size and complexity of my live rock.  At this point, I need help from someone with an intimate knowledge of marine life, and would greatly appreciate your help.  Questions; 1) If I submerge a piece of live rock into fresh water for the 5 to 10 seconds reported in your FAQs, should the fresh water be heated to match the temperature of the tank?
<Approximate is fine>
2) The rocks of concern have turkey wing bivalve mollusks, cup coral, tube coral, coralline algae, hydroids, chicken liver sponges, button tunicates, barnacles, copepods and small stationary dendrochirote sea cucumbers.  Which if any of these will likely die from the brief exposure to fresh water prescribed for the mantis?
<The sponges will likely suffer... If these are not held as particularly desirable, I'd scrape them off during this process>
I have tried, for 8 months now, to get these shrimp using traps and other methods, so I truly appreciate any help you can give.
Sincerely,
Brad in Basalt
<Be chatting, Bob Fenner>

Super salinization shock to drive the 'uglies' from uncured live rock ?   5/9/06
Hello Crew...
<Howdy>
Been reading, researching on starting a new DSB/LR aquarium and saw several tantalizing references to using a brief dunk of super salinated water to drive the hitch hikers from live rock. The snippets I found referred to salinity levels of 1.035-1.040
<Or even higher...>
but were frustratingly brief in their description of the actual process.
<Okay>
Here is my working hypothesis:  given receipt of 30 pounds of uncured Laho live rock from DFS each piece should be individually placed in a container of salt water mixed to a salinity of 1.040 (or there abouts)  and within a couple ( 3 ? 5 ? 10 ?) minutes all the mobile hitch hikers hidden within will 'abandon rock' due to the haline stress.  The 'purged' rock can then be rinsed in fresh water briefly (1 ? 3 ? 10 ?) minutes and installed in the *uncycled display tank*.
<Should work... I'd use the ten minute marks>
Critters in the super-salinated container can then be triaged with acceptable beasties added to the aquarium and the 'uglies' consigned to the compost heap.
<One way of putting this...>
This theory appeals strongly to my sense of how marine invertebrates will react to a potentially deadly environmental stress with over-saturated salinity, but lacking any experimental reports in the published literature or practical empirical experience I thought it might be a good idea to solicit the salacious comments of the widely-acknowledged "Crew of Last Resort" !
Thanks...
John
<Was hoping for first place... Well, this protocol/procedure will likely result in a loss/removal of most pest worms, and crustaceans... with a good deal of the sessile invertebrates left alive... Bob Fenner>

Mantis Question  9/21/05
First of all, thank you for the site.  No other source I have seen offers as many facts and opinions for this hobby all in one place.  
<Great place isn’t it? I’ve learned a lot myself here. Adam J with you tonight.>
I have a new (roughly 4 month old) 30 gallon aquarium with about 42 lbs. of live rock.  My wife discovered a very small Mantis shrimp excavating his home in one of my live rocks.
<Uh-Oh.>
  We have seen his eyes and possibly the first fifth of his body length and from the pictures seen/articles read; I would estimate his total length to be 1" to 1.25".  
<That’s still large enough to wreak havoc on smaller invertebrates and fish such as snails and gobies.>
Is it possible that this specimen could lead a happy life in my tank without causing too much horror?
<Possible but in my experience not likely>
Feeding this guy small pieces of fish has already provided much entertainment.  
<They are cool animals in their own right and make great displays in species only tanks.>
I currently have several snails, 2 peppermint shrimp, 2 porcelain crabs, and an emerald crab.  I have not yet added the first fish but I was hoping to add at least one of the smaller gobies that are less than 1" such as the Trimma (sp.) goby.
<All of these could be a risk.>
My LFS has agreed to take him if he is not "ugly" and I manage to catch him.  The trap I purchased has not yet worked and I refuse to use any spearing or cutting technique (he didn't ask to get thrown into my tank).  
<I admire your respect for the animal, it will take patience but I would remove him.>

Mantis Still on the loose  9/28/05
Thank you for your advice.
<Anytime, that’s what I’m here for.>
After reading your response as well as all the literature I could find, I
decided I was deluding myself that I might be able to leave the little Fellow in a reef tank.
<Every once and a while I hear stories of people keeping a Mantis in harmony with other critters, though this is an EXTREME exception and not at all the norm.>
After having zero luck with a commercial trap, I decided to try the
RO/carbonated water method where each is poured over/into the rock.
<Ok.>
While I had read this is the "magic bullet" the stubborn fellow refused to
budge even after I went so far as to immerse the rock in RO water.
<They are very resilient critters. Keep in mind most of them that are found in tanks have survived dry shipment and curing. I even know of a specimen that survived a copper treatment.>
I am afraid that I pushed the limits and caused the death of the loan coral I had on the rock, an anthelia polyp.  This was the first coral I have tried to keep and it was doing wonderfully.  Though it was my fault for pushing the
limits on the polyp's exposure this experience has pushed me much closer to becoming a "mantis hater".
<I can imagine that this is a frustrating ordeal.>
My question is this:  If I did indeed kill the only coral on the rock, how
long can I place the rock in RO water without losing all the properties that make it "live rock".
<Personally I would not immerse the rock longer than 15 minutes. I usually shoot for around 5.>
After the loss of the coral, I will remove the rock
Permanently if that is what it takes, but it is a rather attractive rock
almost covered with purple coralline algae and I would like to keep it.
<It will take patience. I would try another trap or retry the one you have; sometimes it takes weeks before they work.>
Thanks, Eric
<No problem, Adam J.>

Re: Mantis on the loose ... no more   5/9/06
Greetings Bob,
<Jason>
Thanks for the great advise.  I pulled out each rock last night and dipped them all in fresh water for two minutes.  After it was all said and done I
looked through the water and found at least 20 little Mantis shrimps in the bucket.
<Yikes!>
( they were about 1/2 cm in length and a bluish/green in color)  Just seeing all of them there makes me wonder if there are more or
not but hopefully I got them all.  Once again thank you for your advise! I really appreciate it!  Now there is no doubt in my mind that I can
continue with the tank the way that I intended it to be.
Thanks for all your help!
Jason Chernick
<Congratulations on your "fishing" trip! Bob Fenner>

We think we now have a Mantis Shrimp. Should he live or die 8/28/05
Hi Bob, <James today>
We just put in a large amount of live rock and have heard a clicking sound.
We can see a shrimp. From pages on your site we think he looks a lot like a Mantis Shrimp. <Could be a pistol shrimp also.>
We have two Clowns (one a little bigger and one about the same size as the shrimp), a small anemone, A small bi-color blenny (about the same  
size as the shrimp), a carpet blenny, twice the size of the shrimp and some small brittle stars.
We did have some small crabs but I am likely the snapping sound was their death knell as I can no longer see them. <Sounds like a mantis>
Is there a high chance I will loose fish to this snapping hitchhiker?
<Possibly>
The fish, shrimp and rocks have been together for two days only so far... have I setup the makings for a sad end to my fish.
Would it be best to remove the mantis shrimp for all concerned?
<I would remove it.  They do sell mantis traps.>
I'd appreciate any thoughts you have on the issue.?
<James (Salty Dog)>
Regards
  - Matthew

- What to do with a Mantis Shrimp [is it safe?] -
<Greetings, Jason C here...>
Let me start by saying...mantis shrimp are tricky little boogers!  To recap, I purchased some uncured deco rock, and while curing it in a 20 gallon tank, I heard clicking/popping noises off and on.  The noises stopped, so I blamed my paranoia and imagination (and my husband says I'm in denial!).  Of course, now that the rock has been transplanted to my main tank, the noises have begun again and lo and behold, I have spotted the culprit.  The mantis shrimp is about 1 1/2" long and mostly hides in the rocks, but seems to be
getting bolder by the day, actually coming out into view when I shine a light in his hole.  My current tank inhabitants include: a maroon clown, a strawberry Pseudochromis, a Christmas wrasse, a three-striped damsel and critters include: Astrea snails, a few peppermint shrimp, a green brittle star, a pincushion urchin, a small red starfish and a pink and green cucumber.  I just want reassurance that I do indeed need to remove the mantis shrimp.  Any chance of the inhabitants continuing to live in harmony? <There is a chance, albeit a remote one, I wouldn't risk it myself. I'm sure you've read up on these, but I'll quickly reiterate - mantis shrimp [stomatopods] come in two basic varieties: smashers and spearers. These descriptions accurately portray their offensive capabilities. If your mantis is a spearer, your fish are most certainly in jeopardy as soft-bodied prey is the preferred food of the spearer. If your mantis is a smasher [the clicking certainly makes it seem like a smasher], then it would prefer crabs, snails - things it can bash into submission. That being said, all stomatopods are wily predators and will have no problem taking something not usually on their list. So... the choice is yours. There is also the chance that this is not actually a mantis shrimp but a clicking shrimp, also known as pistol shrimp. These shrimp make a lot of audible clicking sounds, and typically are much noisier than a mantis. If you haven't already, check out our pages on the subject:
http://www.wetwebmedia.com/marine/inverts/arthropoda/stomapods/mantisshrimp.htm >
I think I know the answer, but I don't want to believe it!  As always, thank you so much for the information, the website and the correspondence.  You guys are super-cool! <If I might add one more possibility for you... stomatopods make really fascinating pets, but would best suited to a tank all to themselves. A 10 or 20 gallon tank would suffice. Cheers, J -- >

More light for the tank?/possible mantis (03/12/03)
Hi everyone!
<Hi! Ananda here today...>
I have been working on my second reef tank for about ten months now. I have had very good luck with my soft coral tank (4 years) so I am now going to try a SPS tank. This one is 48X24X18(90G).  I built the hood with three sockets for A future addition of a 250W Iwasaki. The light hood has two 175W 10000K metal halide lamps plus two VHO actinics. I am trying to strike a balance between color AND growth. Would the 150W Iwasaki be enough or would
another 175W 10000K be more appropriate?
<Whoops... you mention a 250w first, then a 150w, then a 175w... each of these bulbs requires a different ballast. Do you have the ballast yet?>
The bleaching of the corallines is an issue with me, because I believe the corals will need the light. Should I add this light to the cycle now?
<No need to add the light when you don't have corals that need it...unless, of course, you read by tank light.>
I added the live rock back in September, and I probably won't begin stocking until May. I almost broke down and added a small school of green Chromis, but on one of my late night "safaris" I think I spotted A mantis shrimp possibly Gonodactylus platysoma (photo on blueboard.com) so I broke down the Q.T. (I will wait and watch).
<I would be setting up the QT to hold the mantis! They are cool critters. Even if you disagree, there are many people who would love to care for your mantis. Do check out the WetWebMedia site and WetWebMedia chat forums for discussions on how to catch and remove these critters, as well as how to keep them or where to sell them!>
The few snails and crabs seem fine.
<Keep a count on them...will help determine/confirm your species diagnosis.>
The water parameters are ammonia, nitrite, nitrate, and phosphate are not detectable. The salinity is 10.25, alkalinity 4.5 m/ltr., and calcium is 450. The water is changed every week at 6%.
<Sounds good.>
I would also like to thank Ananda and one other (maybe Anthony by the sounds of the humor maybe not) for your most recent responses.
<You're welcome... not Anthony, since he always signs off on his... sounds like one of the guys on the crew didn't want to get caught/blamed by your wife in case of your untimely demise!>
YES, I am the guy who spilled skimmate all over his living room carpet. The wife did not kill me (yet)! She just keeps asking me "When are you going to put fish in that d&%m thing?"
<Ah, the cry of spouses of hobbyists with new tanks everywhere... I would suggest you add a couple of clownfish-shaped food clips and point to them next time she asks.>
Thank very so much again Ben.  
<You're welcome. --Ananda>

Killing a mantis with cold...
hello
I've heard that mantis shrimp can't take the cold.  I
was wondering if I let my tank cool down to the 60s or
lower for a few hours, would that likely kill the
shrimp?  all I have so far is live rock.  if you think
this might work, how low should I let the water cool
and for how long?  except for the Aiptasia (another
problem to solve) I wouldn't want the life on the LR
to die.  it's mostly sponges, feather dusters,
Christmas tree worms, turkey wings, and other such
things.
thanks,
warren
<Mmm, I wouldn't go the chilling route. You're very likely to kill more of the desirable "live" part of your rock than the mantis. I would instead try baiting, trapping it/them out. Please read here re:
http://www.wetwebmedia.com/marine/inverts/arthropoda/stomapods/mantisshrimp.htm
and the linked FAQs (in blue, above). Bob Fenner>

Re: killing a mantis with cold...
thanks, bob, for your quick and helpful reply on my
mantis shrimp problem.
<Welcome>
tried the x-terminator over a period of 4 nights using
raw salmon (fresh each night) and then a meaty frozen
fish food, all with no success (or even a nibble!).   
<Yum, am coming over to your place... don't give up here... may not be hungry enough, or like other types of food. Try a bit of shellfish (like a cocktail shrimp piece or oyster...)>
decided to go the tedious club soda route.  first
tried pouring club soda over each piece and into the
holes, but was unsuccessful.  so bought a ton more
club soda and dunked each piece of LR for about 3
seconds each.  that worked like a charm.  got both
inch-long shrimp.   
<Oh! Congrats>
moreover, after 2 days, it doesn't appear the process
has hurt the LR at all.   
<Good to hear/read.>
thanks again,
warren
<Thank you for the follow-up/input. Bob Fenner>

Mantis shrimp (02/20/03)
How do get the darn thing out
<Many suggestions in the mantis shrimp FAQs, linked here: http://www.wetwebmedia.com/marine/inverts/arthropoda/stomapods/mantisshrimp.htm ...more suggestions on the WetWebFotos chat forum (http://wetwebfotos.com/talk/. --Ananda>

Mantis killer
>Hello.  
>>Hello.
>Need your help.  I've recently introduced gulf live rock to my 120gal tank to start my cycle.  
>>I shall assume that this rock has been cured.
>I noticed a few nights ago that there's some clicking coming from the tank.  I have a strong feeling this is a mantis shrimp.
>>I would tend to agree.  Not a good feeling!
>Although I haven't seen it yet, I'd live to dispose of it before I put my clean-up crew in there in 3 weeks.   My question to you is, once my cycle is complete, is there any fish or eel that would make a nice treat out of the mantis.
>>None that I know of that would be reliable, though I've read several recent reports of Coris gaimard that have been seen eating mantis shrimps.  In one instance, the C. gaimard was a juvenile.  These are a hardy, fairly peaceable fish to have, not to mention their spectacular juvenile and adult coloration.  I have found them to be very easy keepers.
>I would like to avoid going the trap route since I hear that most of them don't work very well.  Please help.  Demetrius
>>Yes, the mantis is a very clever shrimp, he is.  What I would do first is begin a process of separating the pieces of rock, in order to narrow down where the mantis may be.  This will take time, space, and energy, but after having one entire reef tank of my own wiped out of all motile inverts/non-cnidarians it's worth it to me.  Be careful, though, these shrimps are known in some locales as "Thumb splitter".  Good luck!  Marina

Will mantis shrimps or bristle worms in any way damage corals or clams? 6/15/03
<Hello, PF with you tonight>
Will mantis shrimps or bristle worms in any way damage corals or clams?
<Ok, I'll break this down:
Mantis shrimp will generally not harm corals, unless they disturb them by walking across them. Depending on the relative size of the clam and the mantis, and the type of mantis (smasher vs. spearer), it could kill and eat a clam. A 2" mantis is no threat to a 10" clam, a 6" mantis is another story.
Bristle worms: in general, no. If they are in plague numbers, they could irritate a corals tissue. As for clams, they have a bad, and undeserved rep. Often a clam with be doing poorly, but still look healthy overall. The clam dies overnight and the worms come out and eat it, the nest morning the aquarist sees the worm shell crawling with worms and makes the obvious (but wrong) conclusion. There are a few species of worms that prey on clams, but they are very rare in captivity.
Bear in mind these are generalizations, you can get a more specific answer with a more specific question. So on that note, have a good evening, PF>

Fight of the Year!  Coral Banded Shrimp vs. Mantis!
>Saludos Salados:
>>Greetings!
>Last week I purchased a CBS and placed him on a 10gal tank. This tank has been running for a year with no apparent problem. The other tankmates are a Cinnamon Clown a Turbo snail and a couple of Bumble Bee snails.
>>Alright.  And now..??
>Recently my wife noticed a strange animal in one of the life rock holes. For her description I think we have a Mantis in the tank.
>>Oh no.. <groan>.  I had a tank wiped out by a mantis once.
>This would explain the disappearance of a Royal Gramma about a month ago.
>>It would explain it quite neatly.
>My question is, will the CBS kill the Mantis or the other way around?
>>My money's on the mantis, hands DOWN.  As a matter of fact, being as how I'm NOT a gambling woman, I would actually put money on that one.
>I am concerned for the CBS (named Jacques) which my son regards as a cool pet to have.  Best Regards; José A. González
>>I would be concerned as well.  There are those who've had luck using different traps.  At the very least (and often the best), if you can determine which piece of rock it's in, then you can remove it to a pail of fresh water.  This will cause the animal to exit IMMEDIATELY, and allow you to put the rock back in sans mantis.  Marina

Bloody Shrimp 12/10/03
Hi;
<Hi Antonio.  Adam here today.>
I have a 3 foot tank, and I have had a mantis shrimp in there. One night despite getting rid of three and a larger one on one occasion, I still have more clicking in the tank. What can I do?
<First of all, don't panic!  Even if it is another Mantis, most that are incidentally collected with rock are smashers (spearers tend to inhabit soft bottom habitat).  While dangerous to small invertebrates, smashers are very unlikely to harm fish.  I would continue to apply whatever trapping method that was successful for you in the past.  Also keep in mind that harmless pistol shrimp could be producing the clicking.
I have heard about dipping rocks in soda water but this can be very detrimental. What is the best way to get rid of them if you cant find them?
<For the soda water trick to work, you obviously have to know which rock they are in and be able to remove it.  I would try trapping first and consider the soda water trick as a last resort.  I would also suggest targeted pouring of the soda water over a total dip.  Please do avoid clearly harmful tactics like prolonged freshwater exposure and boiling water. HTH! Adam>

Who Will Win the Shrimp War. I'll bet on the Mantis (12/10/03)
Saludos Salados: <Greetings>
Last week I purchased a CBS and placed him on a 10gal tank. This tank has been running for a year with no apparent problem. The other tankmates are a Cinnamon Clown a Turbo snail and a couple of Bumble Bee snails.
Recently my wife noticed  a strange animal in one of the life rock holes. For her description I think we have a Mantis in the tank. <Uh oh> This would explain the disappearance of a Royal Gramma about a month ago. <Quite possible.>
My question is, will the CBS kill the Mantis or the other way around? <I'd put my money on the Mantis any day. It has a much more formidable weapon>
I am concerned for the CBS (named Jacques) which my son regards as a cool pet to have. <CBS are way cool. I love mine. Do get rid of that mantis. Start here: http://www.wetwebmedia.com/marine/inverts/arthropoda/stomatopods/mantisfaqs.htm>
Best Regards; José A. González

Mantis shrimp 11/3/03
Hello to all, I have a question concerning a mantis shrimp (little brown type about 2"), I have tried various traps but it is smart and all attempts have failed.
<Hmmm... there is likely no need to remove it anyway. Pause and get a correct species ID (look on the net at the Stomatopod reference sites). Yours is quite likely a smasher (not a spearer) with an adult size of just a few centimeters. If so... it is harmless>
I have not noticed any deaths so I am assuming that the mantis is getting enough to eat without killing my fish, shrimp or snails. Is it possible that it is feeding on copepods?
<microcrustaceans yes... but copepods are rather small. Amphipods more likely. Other larger infauna from the sand too>
Since trapping has failed I have decided to let him be, so my question is what can I put in to feed him and keep him content,
<most any small bits of thawed frozen meaty foods placed near its den/lair>
I was thinking about some blue leg hermits since they are cheap.
<good heavens! unnecessary and a poor use of a living resource. No need, mate... wholesale meats of marine origin are fine - fish food. Best regards, Anthony>

Missing in Action - Must Find That Mantis! 
>Hello to all, I find myself scratching my chin yet again and staring at my tank like the RCA dog, a daily occurrence. I have/had a yellow tail Coris wrasse ~ 5-6" ~ for over a year and he made the move from my 55 to my 125 four months ago without any problem.  In addition I put a three inch two line goby in the display tank last Sunday and haven't seen him since.  I've heard the loathsome intermittent clicking noise coming from the tank since day one and have yet to see the devil.
>>Uh oh.  I know this story all too well.
>I tried to flush it out when transferring the live rock by exposing all the rock to a bath of hyposalinity for three to four minutes per my LFS guidance counselor.
>>Fresh water dipping is generally most effective, but it helps to have an idea of which rock/rock group to go after.
>My question is it likely that the shrimp could/would catch and devour either or both fish in a two to three days time?
>>Hhmm.. depending on the size of the mantis, I'd have to say it's a good probability.  Especially if it found the wrasse, though large, buried and at night.  I'm assuming your tank is well-covered and you've done the search all about, even in the places where "it's IMPOSSIBLE they'd land there!".
>I have check all around the tank, floors, overflows, hood, probed the sand bed, checked the tank with lights off,  looked behind the tank with a mirror.  Ammonia isn't up and I don't know if it's worth breaking down the tank and disturbing the other fish and more than I have to find them or what left of them, ughhh.  :(  Any thoughts or suggestions, and again, thank you ahead of time.  Steve Suniga
>>In a tank that size, even if the fish just kicked with no help from the shrimp it doesn't necessarily follow that the ammonia would spike.  However, as I said, it could be likely that they've been nailed if you're rather certain (the clicking sure is a bugger) you've got a mantis.  In this case, I think it is QUITE worth it to do what you can to find that shrimp.  They can, do, will, and HAVE decimated entire tanks.  I even lost a gorgeous Tridacna derasa to a mantis (just smashed it open, even when it was said it would never happen, it did).  Must find that shrimp!  Marina

Mantis In The Mist (Mantis Shrimp...)
Hello to all,
<Hey there! Scott F. with you today!>
I find myself scratching my chin yet again and staring at my tank like the RCA dog, a daily occurrence.
<Well, as long as you are not scratching other body parts while staring at the tank, then you're on the right track here...>
I have/had a Yellow Tail Coris Wrasse  ~5-6" for over a year and he made the move from my 55 to my 125 four months ago without any problem. In addition I put a three inch Two Line Goby in the display tank last Sunday and haven't seen him since. I've heard the loathsome intermittent clicking noise coming from the tank since day one and have yet to see the devil. I tried to flush it out when transferring the live rock by exposing all the rock to a bath of hypo salinity for three to four minutes per my LFS guidance counselor.
<You could also try one of the "traps" designed just for that purpose...>
My question is it likely that the shrimp could/would catch and devour either or both fish in a two to three days time?
<It is certainly possible...And it is equally possible that you may have more than one...>
I have check all around the tank, floors, overflows, hood, probed the sand bed, checked the tank with lights off,  looked behind the tank with a mirror. Ammonia isn't up and I don't know if its worth breaking down the tank and disturbing the other fish and more then I have to find them or what left of them, ughhh.:( . Any thoughts or suggestions, and again, thank you ahead of time. Steve Suniga
<Well, Steve- short of removing all of the suspected "hideouts" of the Mantis Shrimp and suspending the rock in a bare tank, or dipping the rock in carbonated water, you may need to resort to one of the aforementioned "traps" in an attempt to catch this guy (or guys...). Keep up the high level of alert, and maybe you'll nab the little scourge...Good luck! Regards, Scott F>

Mantis menace
Dear Mr. Fenner,
<Devon>
My husband and I have recently become marine aquarium enthusiasts.  We purchased a 28 gallon tank and have around 35 pounds of LR in it.  We set it up a little over two weeks ago with 100% live sand.  We have 2 medium damsels (for cycling purposes), a hermit, an arrow crab, 2 turbo snails, 2 urchins (stow-aways on the LR), a peppermint shrimp, and an anemone that grew on it's own from the rock.  From everything that I have read and heard, we apparently have at least two mantis shrimp living in our rocks.  We have seen the larger of the two (about 2 1/2-3 inches in length) go after our peppermint shrimp.  From reading on your site and from things that I have heard, it appears that these are rascally little creatures that are very hard to deal with.  The larger of the MS lives in one of our foundation rocks.  Can you tell me the method that YOU would try first to get these little buggers out before the hurt something (especially our arrow crab)?  Thank you for any and all advice you may be able to give me.
Devon Vickers
<If you can definitely see where they are, in this small size system I would gingerly (for fear of bodily damage) remove the specific rocks and flush them out with soda water (yes, carbonated drinking water)... if this doesn't do the trick (next trial) I would try baiting them out with a tasty shrimp (cocktail sans sauce) and fishing line toward evening... with a speedy, sure hand net! Lastly, if these two techniques don't remedy the condition, I would go the plastic (Home Depot, Lowe's) mouse trap route with a meaty bait. Get 'em outta there! Bob Fenner>

Mantis menace II
Thank you so much for your help regarding the nasty little mantis guys.  We got the two that we know of out last night.  Oddly enough, one of them came over and jumped onto the side of the net and climbed right in!
<Hee hee, some Darwin Award candidate in the crustacean class now!>
The other one was a very tricky matter.  We had bait in there, but he was just not going for it.  Finally, my husband got mad and took the whole rock out.  He but it in a bucket and the thing would not come out.  We didn't have any carbonated water, so my husband had to go to plan b, which was to skewer the little sucker, which, he successfully did.
<En garde!>
  Those little guys are vicious!  Anyway, who knows if there are twenty more lurking around in there, but we got the two big guys out.  The smaller was about 2 inches and the bigger one was a good 3 to 3 1/2.  YUCK!  Have a great day!
<Beautiful animals, but destructive in the "wrong" settings. Cheers, Bob Fenner>

How dangerous is a Mantis shrimp?
Hello all, << Hi, Blundell here. >> I have identified a Mantis Shrimp it is a Gonodactylus (little
green 2.5"). I have tried trapping  without success, very smart fella. My
question is what threat/damage could this little fella do. << Overall not much damage.  He isn't going to terrorize the tank and eat everything.  What he can do is eat a few small fishes and pick on some other small invertebrates. >> I am starting to
like him but if he is going to reek havoc of my hermits and snails (maybe
clam) << He may eat some, but people who keep Mantis shrimp often have hermits and snails in those tanks anyway. >> then I will continue on trying to remove. I read in one of the  FAQ
where this species was referred to as harmless, I thought harmless and
Mantis were two words never associated with each other. << Well harmless to your corals.  Maybe not so harmless to little fishes, but then again what is? >>
Thanks again for your time.
<< To remove him, I recommend scaring him with a stick so he hides in a rock... then remove the rock.  If you keep him, I would suggest feeding him every few days in hopes of preventing him from being too aggressive. >>
Mike Winston
<<  Blundell  >>

Help with an Eviction
Please help:
<I'll try! Ryan with you today>
I have a buddy with an 80 gallon bow front. He has had it up for 6-8
months and was loaded with emerald crabs and fire shrimp. They have all
disappeared in the last 2 weeks. Last night he saw a tail flapping
around after the lights went out. Mantis Shrimp maybe! <Prime suspect> If so how in the
world do you catch the little bastard? <Glass trick: Take a pint glass, lean it upright against the rockwork.  Leave a few silversides or meaty item at the bottom, and he'll jump in to get them.  He won't be able to climb back out, but he'll be good and mad so watch your fingers.  If not a Mantis Shrimp, any
ideas? <The tail is a good clue that it's a mantis.  You may even want to set up a small aquarium for this creature- It's quite fascinating.> Everything else seems to be fine. Snails are still there and fish
seem fine.
<Won't be long unless he finds the shrimp! See ya, Ryan>
Brian

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

Rogue Stomatopod, Part Deux...
Hello Tracy,
For any Gonodactylus, or other "smasher" variety Stomatopod, an arrow crab is nothing but a meal. I'm not sure what the logic behind putting an arrow crab in the tank was.
I would try a trap first. If that fails, you can try a hypo saline dip. Mix the water to 1.036 and dip the suspected rock (if you can best guess which rock he's in). Leave the rock in this solution for two minutes, no more. If he's in that particular rock, this should send him scurrying out.
Good luck
Jim***
We recently discovered that we have a mantis shrimp living in our live rocks, her has been coming out every couple of days so we can see him, but he's too fast for us to catch him.  We don't want him in there because of the harm he can do to the tank, so we inquired with our local fish store what to do.  They suggested buying a trap, which they stated had about a 50/50 chance of catching him, or adding an arrow crab to the tank to seek him out and kill him.  We opted for adding two arrow crabs to our 65 gallon tank, they have been there for about 24 hours now, one has already molted.  What do you think about this strategy?  Can you think of anything else?  We had thought of taking out the rocks and running them through fresh water, but we don't really want to kill other stuff living in the rocks, plus we are not 100% sure which rock he is living in (he moves around).  We have several corals, live rocks and a few fish (left!).  Thanks,
Tracy  

Rogue Stomatopod, Part Tres!
We have tried the trap for about 3 days now, the only thing it is doing is
feeding the arrow crabs.  They are scurrying off with the bait every night
and having a feast.  They don't weigh enough to set off the trap even though
we have it set at the most sensitive setting.  Dumb question...how do I get
the water for the dip to 1.036?  I think we might want to try that next.  Do
you think that a fresh water dip is not advisable?  Also, if he doesn't
scurry out of the rock, how do we know if he is dead before we return the
rock to the tank?  We tried the fresh water dip over the weekend on a piece
of branch rock that my husband was sure he saw the mantis go in to.  He
wanted to verify that the mantis was dead and took a hammer to the rock.
Guess what, he wasn't in there!  No more smashing rocks!
Thanks for your help.
Tracy
***You need to add salt mix to the dip water until it reads 1.036. This will be easier on the rock than a freshwater dip. Still, do it no longer than two minutes or so. If he's in the rock, he should come out. However, nothing is for sure and I've seen mantis shrimp drive reefers off the deep end. :) This could very well be "JUST THE BEGINNING" MUAAAHAHAHAHAHA!
Hope not, and I wish you luck. I would keep the trap, and lose the arrow crabs for now.
Jim***

Catching a mantis
We recently discovered that we have a mantis shrimp living in our live rocks, her has been coming out every couple of days so we can see him, but he's too fast for us to catch him. << Seen this happen many times. >>  We don't want him in there because of the harm he can do to the tank, so we inquired with our local fish store what to do.  They suggested buying a trap, which they stated had about a 50/50 chance of catching him, or adding an arrow crab to the tank to seek him out and kill him. << I don't think that will work. >> We opted for adding two arrow crabs to our 65 gallon tank, they have been there for about 24 hours now, one has already molted.  What do you think about this strategy? << I think the mantis is much more dangerous and could kill an arrow crab any time it wants to. >> Can you think of anything else? << Yep, rock removal.  Lots of people just lift the rock out, put it in a bucket and shake it around until he falls out.  Works surprisingly well. >> We had thought of taking out the rocks and running them through fresh water, but we don't really want to kill other stuff living in the rocks, plus we are not 100% sure which rock he is living in (he moves around). << That can be a problem. >>  We have several corals, live rocks and a few fish (left!). << I know other people who have little traps.  They just lend them out free and share them.  Also, they are way easy to make out of acrylic.  So the trap idea isn't a bad idea because you have nothing to lose. >>  Thanks,
Tracy  
<<  Blundell  >>

Catching a mantis
Hello.  Yes, I've been to utahreefs.com and they have some good info
too.  Well, I caught my mantis this weekend using the 5 second dip
method.  He's now in a 3 gallon eclipse all by himself, and not too
happy, I'm sure.  << Can I come see him?>> I need to put some rock in there for him/her/it.
Problem is, after I had everything re-assembled in the JBJ, I heard
another click . . . maybe I was just hearing things.  Anyhow, the mantis
is about 1 inch long total and not all that colorful.  Mostly grey and
maybe a little bit of pink here and there.  It hasn't busted a hole in
the acrylic (yet), for that I am thankful.  I am considering keeping it
permanently.  Its kinda cute.  You are welcome to come take a look at it
and take photos. << Great, I'll give you a call. >>  Where it is now in the 3 gallon with no ornaments
should be easy to get a good shot.  Just let me know.
Tom
<< Thanks, Blundell  >>
 

Compatibility - Update on Their Night Stalker.. Calling Richard Ramirez!
To Salty Dog James (God I love that call name!).
<I've had it for quite some time, don't steal it:)> 
Update on our night stalker. We really like this little guy, so we would hate to part with him but sure we have figured out how he launched his operation. Our tank lights go out before our china hutch (all on timers). When the tank lights go out, the crabs leap into action. However, the hutch lights throw just enough light to create a 'moonlight' effect in the tank, so we are sure this is how our Pixie discovered them moving about, thus started his hunting activities. We now have the hutch and tank lights on the same cut off time hoping that will eliminate the problem.  I tried to research it, and can't find anything indicating Pixie Hawks being night hunters. 
<If they can see, they can hunt. Some fish have excellent night vision. Right now you are playing Russian Roulette. Maybe consider a tank of his own. Getting back to the call name.  I have been in the hobby since 1969. The last six years developing a whitish beard, so my cousin's husband started calling me Salty Dog knowing my love for the salt water hobby. James (Salty Dog)>