Invisible Predator
Hello Crew,
    This is kind of important but kind of not at the same time.  I have a 30 gallon reef-to-be aquarium that I'm setting up and recently had a startling discovery.  I have had blue-leg hermit crabs in the aquarium from early on and I kept finding their remains (just the legs still loosely connected) periodically buried in the sand.  I thought the largest crab, which was actually a zebra crab, was killing the smaller ones.  So I removed him and placed him in my quarantine aquarium.  A few weeks after that I found his remains in my quarantine aquarium.  This aquarium was completely empty except for a few pieces of live rock which are infested with Aiptasia.  Is my invisible predator a mantis shrimp or something else?
<My guess, the former likely>
(note: I have also begun to notice the remains in the main aquarium again.)  I have postponed getting any other inhabitants until I find out what is haunting my aquariums.  Besides helping me identify what it is can you also tell me the best way to treat it?
<Posted... http://www.wetwebmedia.com/mantiscompfaqs.htm
P.S.- I would also like to know how to get rid of the Aiptasia, but only if you have time to put it on here :-)
<... posted... on WWM... use the search tool... indices...>
Thank You in advance for your help,
Andrew S.
<Please, help yourself. Bob Fenner>

Mantis shrimp?
Mr. Fenner,
It's Phil again. While I was looking at my 3 gallon FOWLR tank I noticed 4 or 5 small shrimp, no longer that a pencil tip. They have a black strip on their backs. Are they mantis shrimp babies?? 
<Impossible to tell from here>
I made sure there are no larger mantis shrimp in the tank, so after nearly 8 weeks after adding LR how did they just "appear"? 
<Can>
Your guess is as good as mine. Hopefully this is my last question for a while, I must be driving you crazy. Best wishes to you and all of your aquatic friends. Phil
<Take a look on WetWebMedia.com re crustaceans of all types... might be stomatopods... likely something else. Bob Fenner>

Parasite: to be or not to be
<<Greetings, JasonC here...>>
I just discovered a possible intruder in my salt tank. The tank is a 110 gallon, soon to be reef (it's in the early stages). 
The tank is only about two months old with a TetraTec 300 for filtration. Four feather dusters, six small clown type fish, turbo snails and some tiny hermit crabs make up the mainstay of the life in the tank. Here's the question, the intruder in the tank seems to be living in a piece of live rock and is at this moment feasting on a small turbo snail. 
This creature looks to me like a yellow/green long millipede and seems to be light sensitive. 
<<Have you seen the entire creature? Does it have visible eyeballs or does it look more like a worm? There are a number of possibilities and one is a scourge to some and pet to others [I have one], the Mantis shrimp - do check out the following links:
http://www.wetwebmedia.com/marine/inverts/arthropoda/stomapods/mantisshrimp.htm
http://www.tcnj.edu/~maughme2/faq.htm >>
Any help you can give concerning what it is would be appreciated. I might have to extract the live rock to remove the critter if it's a predator. This creature in my tank must've come in on the live rock. what is it? 
<<Too many possibilities... do check those links.>>
Thanks, Wes James
<<Cheers, J -- >>

Mantis Shrimp
Good Morning,
Thank you for taking time out of you day to answer my question. It is nice to have a source of reliable information. I have 90 lbs of live rock in a 75G tank. Four days ago while gazing into the tank I noticed two eyes peeking out a hole in one of the rocks. Later that evening I heard successive popping/clicking in the tank. The tank is three months old and to date, I have suffered no casualties from the shrimp. My first course of action would have been to pull the rock but unfortunately, the rock serves as a foundation piece and will cause a rock slide if I pull it out. I chose to use a sharp implement and try to skewer the shrimp. I made several unsuccessful thrusts and the shrimp alluded me. I set out a commercial trap (XTerminator) baited with krill later that evening (after lights out) and during the next two evenings without any success. I will try the trap a few more times then I may have to pull all the rock. My first question is whether or not mantis shrimp are partial to their original homes. I have not seen/heard it since my first attempt at slaying it. Will it return to the original hole or just take up residence on another rock?
<He may have moved.>
I have read about the success of using carbonated water to flush out the shrimp. How much damage will I cause the removed rock if I squirt each crevice/hole of each rock until I find my target?
<Doing every rock in your tank maybe a bit extreme. Try to narrow it down a little first and keep trying the trap with various baits.>
A somewhat unrelated question. If I have to remove all the rock it might be a good time to add live sand to approach a DSB. I currently have about 1.5 of crushed coral. Should I add live sand on top of the coral or remove completely?
<Remove completely and use at least 4" or more of fine sand.>
Thank you for your help.
<You are welcome. -Steven Pro>

Mantis?
Hi, how are you guys today?
<Pretty well, thank you.>
I think that we have a mantis shrimp or some other hiding predator in the tank. Hermit crabs turn up with little holes in their shells, and crabs mysteriously disappear... Do you have any advice that how I can go about catching this predator? Thanks for any info. you may have. Marci =-)
<There are various traps you can find at your LFS. Also other ideas and recommendations can be found here, http://www.wetwebmedia.com/marine/inverts/arthropoda/stomapods/mantisfaqs.htm -Steven Pro>

Mantis with Deceptive Names and Curlicue Anemone Digs
Fuzzy Lumpkins is getting bigger digs, and Bun-bun is going to a new home, as soon as his new owner sends me the shipping money. As crazy as this sounds, I spend
to much time in my mantis tanks to want to play tag with a critter that packs a sting. 
<and I really can't wait until you move onto toxic animals that you can lick <smile>>
I'm even moving the zoanthids out, though part of that is the larger tank can take their feeding much better than the nano.
Thanks again Anthony! talk to you soon, P.-F
<My pleasure, Pinky. Antoine>

Snowflake Moray as Mantis Shrimp Hunter
Bob,
Had an additional question and also wanted to say how much I liked your site.
<Okay, thanks>
I was thinking about adding a small snowflake moray to hunt down any mantis
shrimp in the tank. Will the snowflake eventually find them all?
<If "they're" small enough, the Eel hungry enough, possibly>
Thanks again, Marc
<Be chatting, Bob Fenner>

Crabs with Mantis
I just moved 2 emeralds and a sally lightfoot out of my tank due to fear of them eating fish. Would they be able to hold their own in my other tank, which I will be adding a peacock mantis shrimp to soon?
<that is pretty crazy on both counts, my friend (especially for the sally)... the crabs are unlikely to harass any HEALTHY fish, and they are unlikely to survive with a mantis. Anthony>

Re: Crabs with Mantis
> I just moved 2 emeralds and a sally lightfoot out of my tank due to fear of
> them eating fish. Would they be able to hold their own in my other tank,
> which I will be adding a peacock mantis shrimp to soon?
> <that is pretty crazy on both counts, my friend (especially for the
> sally)... the crabs are unlikely to harass any HEALTHY fish, and they are
> unlikely to survive with a mantis. Anthony>
ok if you think so. I have just heard others accounts of sally Lightfoots and Emerald Crabs eating like one inch clowns. Based on your response, I guess I will put the sally and emerald back in. Thanks
<really just a judgment call but do resist from moving any creatures repeatedly in such a short time... some hardy creatures can die that way. Technically anything that comes from a reef is not reef safe. Everything on a reef must eat something else on a reef (no take-out food, eh?). It then is a simple matter of if we find their "dinner" desirable or not that skews our perception of reef suitability. We have all heard stories of some dwarf angels and Zebrasoma tangs eating coral while other of the same species do not. Our captive reef denizens unfortunately do not read the same books that we do <smile>. Just weigh your options... do you need the algae control more than you fear their risk to small fishes? I think it is fairly safe. At least as small fishes go, they are safer from crabs than they are from Yellow and Sailfin tangs... hehe. Mean little bugger sometimes! Anthony>

Live Rock
Good Day- Mr. Fenner
<Anthony Calfo in your service>
I was just wondering if I were to buy some more LR and put it in my tank and a mantis shrimp were to show up would it put my other fish in danger or kill them? 
<very unlikely with the below listed fishes... but you did intend to quarantine/cure it first in a separate tank didn't you? It would not be very responsible to put rock in directly considering the great value of the fishes at hand, not to mention their very lives, to indiscriminately put un-cured live rock/sand/or new fishes in so casually. Too great a risk of parasites, pests and predators that way>
I have a 7" Adult Emperor Angelfish, 4-5" Clown Trigger, 4-5" Miniatus Grouper-2 blue damsels which he will finish up in a few days and a 4" Tomato Clownfish. I already have 130lbs of LR and am wanting to add 30lbs of Fiji or Tonga LR - I have 135 gallon tank.-Thank you for your help-Ian Behnk
<kindly, Anthony>

Live Rock and Mantis
Dear Bob,
<Anthony Calfo in your service>
I am expecting a delivery of 60 lbs of Florida aquacultured live rock for my 75 g fish only tank.
<you will hold it separately at first to make sure that it is fully cured, correct? Never place air shipped rock directly in a display... plus it helps to bait and screen for pests and predators>
My question is, is this rock more prone to Mantis shrimp than say Pacific rock.
<nope... mantis are circumtropical... if anything, one of the more common species seen in aquaria is a little green fellow that never grows to even 2" and is completely harmless...even cute>
Either way, what is the best method of getting rid of these critters before placing the rock in the aquarium.
<suspend the rock on egg crate and bait nightly with meat food tied in a nylon stocking with a fishing line...many other ways too>
I have heard of various methods ( hi salinity dip, fresh water dip) but I'm concerned about all the good life on the rock.
<it will destroy far more good than bad... you are correct>
I look forward to your response and thank you in advance. Rocco
<kind regards, Anthony>

Someone Wanting to Get a Mantis Shrimp
I was wondering if you could tell me where I could purchase a Mantis Shrimp for my aquarium? A spearer is preferred.
<I would talk to your LFS. They get these a lot as hitchhikers on liverock and if you are nice, you may get one for free or at least real cheap.>
Thank you for your time and help. -Casey
<You are welcome. -Steven Pro>

Mantis shrimp
Hi Mr. Fenner,
<Sorry, but you Reached Steven Pro. Anthony Calfo and I are helping out while Bob is out of town.>
Just to let you know your site is very informative and is also a big reason as to why I started up a marine aquarium.
<I will certainly pass the compliment onto Bob.>
Anyways, I just have a couple of questions, the first regarding the pesky little mantis shrimp I think, has taken residence in my aquarium. Recently I've had an Ick outbreak in my 60 gallon aquarium. Following the advice of my LFS and your site I've decided to "nuke" the tank and was just wondering if the mantis shrimp would have survived the copper treatment.
<Probably not>
Secondly I was just wondering what your opinions are on the Built in filters In the DAS aquariums (i.e.. are they sufficient?) as I have been eyeing a 100 gallon DAS aquarium with a built in filter.
<I do not like them. I do aquarium maintenance for a living and these filters are small, cramped, and difficult to service. It is also very difficult to upgrade or make changes. I prefer a tank with a sump.>

The siege begins... (stomatopods at the gate!)
Greetings again to my most respected source of knowledge for home aquaria,
Tonight I was dazzled, amazed, and horrified when I placed the Mag-lite to the glass and witnessed the nightlife of my 7 month old 40 gallon high. To think, for all this time I have been only getting half my money's worth!
<Perhaps not even this much>
Hundreds of baby mysids danced about the bright beam of my torch, the cleaning crew plodded diligently along the rock and sandy bed ... and then these little denizens caught my eye. They scuttled about the pores of my Namoli rock at the speed of a cockroach's sprint. The largest was shy of 2 cm the smallest, less than one half a cm. They left me with the impression of a centipede as they darted for some small holes. Though curious I snapped the light off musing to myself about what they might be (definitely of a decapod influence it seemed). I had to go back, and go back I did. My beam trapped one in a shallow hole (the largest creature). He had an arched posture and performed rapid somersaults in the hole, perhaps searching for dark sanctuary. Realizing no escape from the obtrusive light it presented its face to the bulb with a leer of utter contempt. It had a familiar face, insect-like with antennae perched atop it's head. Hmmm... and the claws ... they hook- MANTIS SHRIMP!!!!!! so it was pink, not green. I knew there would be hundreds of species and as I looked it up, I was right. The larger one had a pink body with darker red "plating" whereas the smaller ones were more of a dull gray. I'm no authority but the way it held its claws (tucked under as the archetypical Stomatopod) convinced me. It was fast, threatening, almost
fiercely beautiful.
<What exciting writing! You really should be doing this for the aquarium press>
I would turn off the light, pace frantically, return and it would be millimeters from the hole, only to duck back in. finally I ran to the kitchen and retrieved 2 plastic cocktail toothpicks. He looked on with fury as my appendage (now armed as its was) slinked towards the illuminated crevasse. I stabbed, not from malice, but from the fear that this would one day grow up to snare my mandarin, or my jeweled rockskipper, only the little nook narrowed and as I withdrew it poked its little head out in triumphant mockery. I jammed in again knowing I wouldn't reach but I was out of options. Another smaller one foolishly scuttled in an adjacent hole and I performed the same procedure with the same scenario unfolding. Regardless, I had a plan. I couldn't kill them, but assuming those little nooks were dead ends I could at least trap and starve those wondrous little bastards ... the siege begins.
<Indeed>
(1,001 apologies for the long-winded manifesto, let's blame sleep deprivation.) Question #1: Does the description fit? 
<Yes>
Question #2: Assuming they can't escape how long must those unsightly toothpicks remain on guard in my aquarium?
<Weeks to months...>
Question#3: There were others, I don't know how many (I saw at least six small ones). How much trouble am I in with a few of these running around?
<Hard to say w/o knowing the species... re their ultimate likely size/dimensions, and propensity for fish-nabbing... But I would look into traps for catching them out...>
Thanks again for all your help (both directly and indirectly) You have made deep impression on my (as well as countless other's) experience in this hobby with all the knowledge you so gracefully impart.
<Thank you for your input, participation, sharing. Bob Fenner>
Your friend and fellow pupil, Brad.

Re: The siege continues...
Greetings again (and thank you for your prompt response).
After receiving 3 hours of sleep I went over to my LFS and relayed the same info. He confirmed my fears as well and I think the two of us concocted a true harebrained scheme (that I hope just might work). I have heard that successful anti mantis tactics include traps (not sensitive enough for these tiny critters), stab wounds (too many creatures too many holes), and rock removal where one would apply freshwater/club soda/the hose from a pump... (would compromise all my rockwork consisting of delicate corals, etc.) Having dispelled all conventional wisdom I have out of desperation temporarily (I hope) acquired a small snowflake moray as I understand they make short work of these fearsome predators. So the question of all questions: what do you think?
<Might work>
The risks are toppling rockwork (he's small, few worries here), the previously mentioned rockskipper and mandarin along with assorted hermits and 2 cleaner shrimp. Is it likely that my system (40 gallon high) won't be badly disturbed by the new boarder or did I perform the "old lady that swallowed the fly" bit?
<Probably okay... if the Snowflake isn't too big (up to the teens of inches... It won't eat your fishes... probably not the Hermits... unless they're out of their shells>
I feel that if I am correct that all other tactics won't get rid of these mantis shrimps (and I'm pretty sure they won't) then I had nothing to lose, since it would only be a matter of time before the mantis grew and destroyed everything. Would like to know your thoughts, suggestions on the matter. Also the next thing I do to this tank will be done on a full night's sleep-- I promise. --Brad
<Sleep, rest my friend... there are baited traps we can make that will make your system Mantis/Stomatopod free if the Eel doesn't do the trick. Bob Fenner>

Stomatopod siege: The battlements crumble
Hello again.
I wanted to update you on the "siege" and get your advice on the present situation. Despite the introduction of the snowflake moray two weeks ago tiny mantis shrimp sightings still continue. An interesting (not to mention perplexing) phenomenon has also developed with the introduction of surround sound in my living room. I have never heard the characteristic pop of the claws that occurs with the smasher varieties in my tank. Today, day four of my action film festival with the home theater, I heard something. In the silence that ensued after a fierce and reverberating small arms exchange on the TV, I heard a pop. A few minutes later I heard another. Within an hour I traced the sound source to the tank (which is terrifying considering that I have the speakers on at full tilt) and they would happen frequently throughout the day. What was perplexing was that this was full daylight regarding the photoperiod. Also the pops were singular in nature, one pop would occur every 15 minutes to an hour, rather than a succession of 3 or 4 in a short period of time (something I'd expect from a pistol shrimp, not a mantis). I wondered if the home theater had awakened a dormant bruiser that I never knew I had. Anyway this drama ensued after the lights came off, and a few hours later I jumped up. After splashing the rock with my Mag-lite I discovered more of them than I had ever seen. The popping had frayed my nerves and at last I encountered that same Stomatopod that I wrote you about that first night. It looked on smugly with a cool assurance of its invincibility and that's when I lost it. I quickly flicked off the snails and hermits from the porous rock where it and many of its kind favored and tore the porous sanctuary from the reef heedless of the destruction I had probably caused and tossed it in a dry bucket. I heard about the club soda trick where
you need to know the exact hole the mantis crawled into and you baste that hole with club soda. That's baloney. You don't need to know which hole. If you spray that stuff indiscriminately I promise you will flush it out/kill it without any need for pinpoint accuracy. The club soda worked like cyanide gas! About thirty corpses were found in the bucket (mind you the largest was barely over 1 cm and the smaller ones were the size of juvenile mysids).
Now that my psychosis has subsided I am left with three large problems. First there is all the damage to the reef that I caused-- man, I'll feel that in the morning. I returned the rock to the tank. Is it safe to return the rock due to potential die-off?
<Likely no problem... not detectable>
The second problem is the eel, as in the determining best way to remove a lazy, deadbeat, (but personable and attractive) 14 inch moray from the tank without disturbing everything, as in the present case. 
<Perhaps in a longer term, trained to feed then netting from underneath approach>
Finally and worst of all, I only got the dominant guys with that rock. Plenty crawl amidst other rocks and their time will come to grow in the tank. I know I can't dip all my rock in club soda -- that would kill everything.
<Mmm, not everything>
The problem is that most of these shrimp are tiny: the size of young mysids (smaller than ants). You mentioned a knowledge and or possession of traps. Do you have (or know how to make or procure) such traps that can contain such small critters, and can eliminate such a large number?
<Possibly... I would make some "pipe bombs" (to borrow your leaning) of sections of PVC (about 4-6 inch lengths, 3/4" diameter...) with Ehfi-Grob filter material (Eheim product) jammed in them... with a bit of shrimp or fish flesh in the middle or so... and place these in the tank toward nighttime, pull them out later (a few hours)... hopefully with stuck stomatopods in them... Even the ole' small Coke (tm) bottle with meaty bait at the end, tilted on its side, placed at the bottom is worth a try>
I have an X-terminator but know it's useless since it's not sensitive enough to catch
such small guys.
<Yes. Bob Fenner>

Re: Deadly Mantis
That's half the problem, I can't find him I have so much live rock. Would you dip the rock or soak it? and in which one? Will either kill everything else?
<If baiting, trapping has not worked... I would go the route of dismantling the system systematically, dipping each piece of rock (pH adjusted freshwater will be fine or hypersalinity seawater...) and locate, eradicate this nuisance once and for all. Have you read the Stomatopod section, FAQs on WetWebMedia.com? Bob Fenner>

Re: Deadly Mantis
Yes, I have. Thank you very much for the information as always. Someone's getting a dip tonight.
<Good hunting my friend. Bob Fenner>

Mantis shrimp
Hey there-
I'm looking for a supply of particular mantis shrimp to include in scientific experiments on color vision and color signaling.
Specifically, I'm looking for stomatopods of the species Odontodactylus scyllarus and Gonodactylus smithii. Since you obviously know a fair bit about the creatures, I was wondering if you knew of reliable suppliers where I could obtain about 30 or so.
Thanks very much for your time and effort. Alex
<Do know of these animals. Will refer your request to these companies. Make it known if I may be of further service. Bob Fenner>
Alexander G. Cheroske
Dept. of Biological Sciences/Marine, Estuarine and Environmental Sciences
University of Maryland, Baltimore County
Baltimore, MD 21250
cheroske@umbc.edu
Phone: 410-455-1634; Fax: 410-455-3875

Deadly Mantis
I have a mantis in my tank that is literally killing everything, snails, fish, crabs you name it. I've tried to bait him out, bought commercial traps, pulled the rock out he was in but keeps jumping out even with a net under I can't get rid of him. I'm ready to tear what's left of my tank down and sell off my remaining fish. My last hope is if you know of anything I can dip my rock in to make him bail? i.e. high salinity, fresh water, anything?
<These will work... but if it were me, my system... and this particular individual is as wily as you say, I would haul it and its rock our and skewer it with a sharp implement. Game over. Bob Fenner>
Thank you, Ken

Mantis shrimp
Hi, I have a question. I have just read the FAQ section on mantis shrimp. I have one in my reef tank he's taken all my snails a coral beauty and a fire goby so on so forth if I try dipping the rock in fresh water will this harm anything else that is growing on the rock such as feather dusters spaghetti worms???
<Yes to a freshwater dip harming other life forms... and it unlikely ridding your system of the Mantis. If necessary, desired, I would systematically (watch your hands!) remove your live rock, and pries (with a tool), remove the crustacean... I am sending your Stomatopod query to our Mantis Maniac/Expert, Mike.B, for his further input. Be chatting. Bob Fenner>
thanks in advance, Joe

Re: mantis shrimp
Hi Joe,
While I like mantis', I'm sorry to say that they really don't have a place in a reef tank with fish. Sorry to hear about your losses. As for getting your uber-predator out, here's my advice:
Getting it out of your system will make this a lot easier. So, find the hole in the LR that the little bugger is living in and then put the LR in an appropriately sized bucket, make sure you can get easy access to the hole.
Trying to fish one of these guys out of the LR can be a pain. You now have the upper hand though. Depending on your goal you have several options:
If you want to make a live capture:
get a turkey baster and some carbonated water. Inject said carbonated water into it's lair, just shooting it in from a short distance away (like several inches) should do the trick. From all I've read, they usually come shooting out of there like a rocket.
If this works (remember, these are very intelligent animals, there's some debate as to who is smarter, octopuses or mantises), you now have it at your mercy.
If you want to execute it, I'll leave that up to your imagination. OTOH, there are plenty of people on reef Central's mantis list who would be willing to give it a home and gladly pay shipping and packing costs. Or, if you can forgive it for acting as nature intended it
to, you can give it a home yourself. They're easy to keep, and very interesting animals.
<Ah, well-stated>
If you want to just kill it: I've heard that this is a great method:
before taking the rock out, remove a quantity of tank water. Refrigerate this till it hits the temp of the refrigerator. You'll have to decide how much water to use this way, here's what you do with it. Using some rigid tubing to direct it, and some flexible tubing as a conduit, setup a drip line into the critters lair. mantis's can't take cold temps and this will eventually kill him (5 minutes was the number I saw with this method, YMMV). You might have to flush water through the LR to remove the body, but this will kill it.
Other options include buying and using a commercial mantis trap. you can order them online or get them at some LFS's. There are also plans out there for DIY traps too.
The best advice I can give is this: go here
http://www.blueboard.com and read up on them. I believe that it is easier to defeat an opponent if you can understand them, and The Lurkers Guide is the best source of knowledge I know of (besides spending a lot of time talking to Dr. Roy Caldwell, THE mantis expert). It also has good advice on getting them out of your tank.
I hope this helps, and best of luck! Let me know how it goes, PF
<Well done Michael. Thank you. Bob Fenner>

Mantis questions
Good night,
I hope all is well. I checked your website about info on mantis shrimp, for after purchasing some live rock recently, I found one. thank God he was in a rock cave when I saw him. I immediately took the rock out, and after a test of patience I got him out. Right now I have him in a small cup which has access to the tank water, and is oxygenated and filtered. However, I feel badly for the mantis, because he seems so confined in the cup. I was wondering to what extent is he detrimental to my tank.
<Mmm, depends on the species of Mantis... what else you have, intend to keep in your system.>
I was wondering if I could release him back into the tank for now, without fear of losing anything. Currently my stats are a 10g, 9 lbs live rock, extremely live rock, with tunicates, featherdusters up the wazoo, numerous worms, baby crabs, 2 hermit crabs, Caulerpa (doubt he'll bother that), a colony of small flower looking corals (forgive my ignorance, they came in on my rock, and I'm not sure what they are) , a small rock anemone, and barnacles. no fish. (if I get any it will be a fire goby, which I imagine then I'll have to remove the shrimp because he'll eat such a small fish) and I plan to get other inverts i.e.. stars, cukes?, and if any shrimp then Lysmata, maybe some other sessile inverts. but those plans are later. so can I safely release the mantis back into the tank until later?
<If you don't mind possibly having to "fish" it out later>
I don't want to kill him, give him to the LFS, because they'll kill him, and I don't have a tank for just a shrimp that's only a few inches long. Any help would be greatly appreciated. thank you, and sorry for the long post. Sincerely Erik 
<No worries. Do consider having the Mantis as your primary "centerpiece" of this small system. It will likely eat any/all fish life introduced, but leave algae, most attached invertebrates alone. I am sending your note to a "Stomatopod fanatic" friend for his further input. Bob Fenner>

Re: mantis questions
Hi Robbie,
Consider yourself among the lucky, fishing the mantis out that fast. They are very interesting animals (I suggest you go to http://www.blueboard.com to learn a
lot more about them) and very hard to catch in most cases. Mantis's come in 2 flavors: smashers and spearers. Spearers eat fish, smashers eat shelled animals, but both can and will eat the others preferred food. You can tell which is which by the shape of the claw, most that come in on live rock are smashers though. If you're willing to live with the loss of snails and hermit clean up crews, they make interesting pets. They won't hurt your corals, as an aside, it sounds like you zoanthid polyps on your rock.
I'm doing a 10g dedicated mantis tank myself. Dr. Roy Caldwell (THE mantis expert, he's studied them for well over 25 years) keeps them in containers in his lab, no filtration just dedicated water changes. If you do decide to keep it, please don't keep any fish in with it, it will eventually eat them. If you do decide to give it up, Reef Central
(http://www.reefcentral.com) has a mantis shrimp board. Someone would gladly take the mantis off your hands, just be sure and get your shipping money up front, one individual shipped without payment, and is still waiting to get his money back. Heck, I'd offer to take it myself but I've already got 2 lined up and don't want to be greedy ; )
Mike (aka PF)
(btw Bob, I'm deeply flattered that you forwarded this to me, you weren't kidding about that long ago threat were you? "hang around long enough and you'll be
answering questions..." : ) )
<Thank you much for your input here Mike. Bob Fenner>

Mantis Shrimp
Hi Bob,
I appreciate all the information and answers that you make so available to us in the hobby...thanks!
<You're welcome>
My question is about the ever present in live rock pest, the mantis shrimp. I have previously managed to remove one from my 75 gallon FOWLR tank by taking the rock out of the tank and dipping it in a freshwater bucket until the shrimp came out (just a few seconds). I now have one or more in my 305 gallon FOWLR and LS (Reef filtration - a Wet Dry with no bio balls and a protein skimmer and two UV sterilizers). I have tried trapping it with the Mantis X Trap and managed to traumatize my Lunare
wrasse, how can I get rid of it or them short of dismantling the whole tank? (300 lbs. of live rock, 200 lbs. of lace rock and 300 lbs of live sand w aragonite mixed in),
<This is a task... I would very lightly feed the tank for days, and then nightly be ready with a boiled shrimp tied to a ten pound or so tension strength fishing line... and either a big, sturdy net and/or a multi-pronged spear (oh and a flash light and maybe a friend to help keep vigil). Place the shrimp in a tank corner (in the front). Keep a tether on the line... and be ready to pounce>
Is there a fish or invert that will eat them? I currently have 10 fish thriving in the tank, mostly grazers... purple, Kole, Naso and regal tangs, flame hawk, Asfur angel, Sebae clown, lawnmower blenny, watchman goby, Lunare wrasse a brown crab and small
starfish along with some snails. Your suggestions would be most helpful.
<Mmm, is the Mantis smallish (a few inches?). Perhaps a triggerfish would get it before going after any of your fishes... Bob Fenner>
Howard Cushnir

Crustacean ID site
Hi Bob!
Whilst looking over the Lurker's Guide to Stomatopods, I found this link:
http://www.crustacea.net/delta/crustace/index.htm
Thought this might be a good place for you to point those coming to you with: "What is this thing?!?" questions. Hope it helps! Mike, aka Pinky Finger
<Thanks mate! Will post as part of the bibliog.. of Mantis (your faves) manana. Roberto F>

Mantis image
Hi, I'm trying to start a web page with mantis images for people who keep them as
pets like me.
<Good idea for a series of articles for the fish magazines as well...>
I was wondering if you minded me using the two image you have on your web page for my web page. Full credit will be given to you plus I will have a copyright clause.
the pic is here: http://www.wetwebmedia.com/mantisshrimp.htm
thanks, Adam Phillips
<A pleasure to be a collaborator. All images are free of use to any/all non-profit uses. Thank you for your just inquiry. Bob Fenner>

Re: mantis image
Your help is appreciated. I always think its better to ask before using as it is your work and I don't like using without permission
<Yes. Civil and honest thing to do. Bob Fenner>
thanks again, Adam

Stomatopod identification, Gulf Region
Hi Bob, it's Pinky Finger again (feels a little weird to be sending this instead of posting to the forum...I'll shotgun this one out there too)
<Good idea>
As I've mentioned before, I'm setting up a Stomatopod species tank, from the Gulf region. Would you be able to recommend any good identification guides?
<Paul Humann and Ned DeLoach's "Reef Guides"... s/b able to find from the e-tailers>
The company operates on a "catch as can catch" basis in regards to 'pods, and I really doubt they'll be able to ID it for me, since they pointed me at the Lurker's Guide when I asked them. As always, your help is appreciated!
<Hmm, there are four or so: Lysiosquilla scabricauda, L. glabriuscula, Gonodactylus oerstedii and G. curacaoensis...>
Mike,
btw, when I finally get this thing up and running (hopefully in about 7 weeks), would you like pictures?
<Oh, yes. In fact, a website. Bob Fenner>

Stomatopod question
Hi Bob, Mike again (you should start handing out nicknames for all of us Mike's, easier to keep track of us that way)
<Hmm, maybe>
This may well be a question you've never had before. I thought that as practice for my eventual larger set up I'd keep a Stomatopod, given they're reputation as "cockroaches" of the sea I thought a smaller setup would work well. I've read the WWM postings on them and the Lurker's guide, plus whatever else I've come across in my wanderings. I was wondering if I could get the official Robert Fenner Stamp O' Approval on this for a species setup for keeping one of these buggers:
An Eclipse system 12 for the tank and mechanical/biological filtration, a Pro-Heat Titanium Heater (no danger of broken glass there)
<Good idea>
A power head for additional current (300 gph?)
<Okay>
20 lbs of substrate (I'm shooting for enough for it comfortably dig a burrow)
<Make it "mixed grade" with some larger (pinkie finger, your new nick name btw) size pieces>
20 lbs of live rock
10 lbs of live sand
I was thinking of ordering from Tampa Bay Saltwater and doing a pure Florida biotope setup, getting one of their 10 gallon packages. I'm aware that the included cleanup crew will probably be mantis food,
<Yes>
but one can always hope. I know bigger is better, but I'm looking for a small scale system to practice with, and I figure the work involved in keeping a smaller system going would be good training to create good habits for keeping my larger system. As crazy as this sounds I was also wondering about breeding them. Just how big of a tank would be required to keep multiple individuals, esp. Lysiosquillina maculata?
<Several square feet of bottom per individual>
I know they're compatible as pairs, but I'm not sure about most of the others.
Well, I'm done rambling now, and as always, thanks! btw, I'll be ordering the Conscientious Marine Aquarist and A Fishwatcher's Guide to The Saltwater Aquarium Fishes of the World, Amazon upped the price on them by about $3.50 but now there's "free shipping"
<Sounds reasonable>
if you order 2 or more items. In the words of Paul Simon, "who do they think you foolin?". Anyway, it still beats the LFS's prices out here, the best I deal I could find was $55 for the softback on CMA.
<Wowzah, I'm going to sell my copy! Be chatting. Bob Fenner>
Thanks as always, Mike

Mantis Shrimp Trouble
Bob,
I have a Mantis shrimp problem. Apparently I have had this Mantis for quite some time, about 8 to 12 months, although I just discovered him about 3 months ago. I happened to catch a glimpse of him one day, but have never seen him again. I have now had two expensive fish just disappear, never to be found, in the last 4 months. I am assuming that they have perished at the hands of this Mantis. The most recent loss was a 4" Harlequin Tusk about 2 days ago. His body has vanished, without a trace. I did try a trap for a few days, without success.
<Hmm, that's a big fish/meal to go entirely missing... Yikes>
This is becoming quite frustrating. Can you offer any tips for getting rid of this menace!?
<Do have a bunch posted on the "Mantis FAQs" part of the www.WetWebMedia.com site. Please read over the suggestions there for trapping, baiting this animal out>
Thanks for you help, Kevin Austin
<Steady on my friend. Bob Fenner>

Mantis Shrimp link
While touring WWM, I stumbled on the mantis shrimp page and was just fascinated... not that I want one in my tank at the moment but...
If you want to put up a web link, I found a good one:
http://www.blueboard.com/mantis/
Lot's of color photos which show this beastie is perhaps the best looking
"scourge" I've ever seen. Wouldn't mind keeping one all by itself... Cheers, J --
<Thank you for this. Will add it to the Stomatopod/Mantis section. Bob Fenner>

Mantis pictures
Do you have any photos of bristle worms or mantis shrimp that I can access?
or do you know of any websites which would have pictures of these creatures.
thank you
<Yes, there is an assortment of these on our site: www.WetWebMedia.com under their associated names... and likely Links under their bibliographies, FAQs pages. Bob Fenner>

Tank problems
I happened upon your website and hope you can answer a few questions for me.
<I will try>
I have a 75 gal tank that has been established for over 8 years. In the last year I developed an algae problem. I have both the course algae that's about an 1 1/2 inch long and the slimier green algae. 
<Actually likely a/some types) of Blue Green aka Cyanobacteria... very common in "older" systems...>
I've been really lax about testing my water over the past years because I regularly did water changes every 4-5 weeks and everything was doing really well.
My tank has in it:
6 line wrasse
Flame angel
2 Percula clowns (laying eggs ALL the time)
Square Anthias
Royal Gramma
Cleaner Shrimp
Coral Banded Shrimp
Carpet Anemone
2 bubble corals
leather coral
assorted mushrooms
Caulerpa
a huge octopus coral
elegance coral
I have a protein skimmer, compact lighting, UV sterilizer
About 6 months ago I started adding a phosphate reducer after testing for it and finding it was a little high.
I've cut back on the amount of food I'm feeding
Nitrates are fine
Calcium is 450
Ph has been a little low so I've increased it this past month.
I've started adding some vitamins, stronigim?? <strontium> Iron, trace elements and have seen everything perk up.
<Ah, good>
Here's one of my questions. To try and help the algae problem, last week I purchased
18 blue leg crabs
Emerald crab
Turbo snails
2 scarlet crabs
<Good choices>
The carpet got a hold of a few of them right away. Is this going to be a
continual problem? Am I wasting my time and money? Is the carpet going to eat all of them?
<Doubtful>
I also purchased a Porites rock with feather worms.
Shortly after I put it in the tank I spotted claws and eyes peering out of 3 of the holes.
Do you think these are Mantis shrimp? 
<Maybe, how could a person tell?>
I put it in my quarantine tank and tried to kill these critters but they can bury too deep into the holes to get. Do you think they're Mantis shrimp? 
<Perhaps a sharp implement routing out the holes will eliminate the need for the question. If they're very small crustaceans, likely your six line, cleaner or Boxer shrimp would/will consume them...>
I don't know much about them other than you don't want them in a reef tank!
Do you have a specific brand of additives (vitamins, trace elements, etc.)
that you think works good?
<A calcium reactor for pH, biominerals like Calcium, Strontium, Magnesium, Alkalinity (carbonates, bicarbonates)... vitamins, other minerals through foods, perhaps iodide supplementing occasionally (once a week)... for vitamins Selcon/n, Microvit, VitaChem... added to the foods.>
What are your suggestions?
<Actually, to add another box or so of new live rock... to "upset", re-set much of the chemical, physical and biological dynamic in your system... perhaps to add a lighted sump with live rock, macro-algae... the periodic use of activated carbon (like a "unit" of ChemiPure, or better the HR (High Retentive) AC of TM (removes even phosphate) in your filter flow path, once a month... You're doing fine otherwise... >
Thank you for your time. Jami Spitz
<Thank you for relating your experiences so lucidly. Bob Fenner>

Unknown Creature in my Live Rock 
Dear Bob 
I was reading some of your articles on WetWebMedia web site in hope of  identifying a living creature I have found in my Live Rock. I purchased  this piece of Rock about a week ago and up until today have not noticed it. 
<Many surprises in this wild-collected material>
The Creature appears to be striped and is about an inch and a half long  with two long tentacles which appear to have its eyes on top - with 6 - 8  small feelers around the head area with lots of pairs of shrimp type  looking legs - Seeing as I have no idea what this creature is I am not sure  whether it is beneficial to my tank or whether I should replace this rock. 
It seems to be burrowing into the rock. I have called my supplier who  seems to think it would be nothing harmful but on closer inspection I am  not so sure. I am relatively new to salt water aquariums so any  suggestions to what this creature may be would be appreciated  Sincerely, Hayley Weighill  
<Hmm, unless I'm very sure of an unknown creature's identity, likelihood to cause damage, I'm inclined to leave it be, and hope for the best... This may well be a type of worm, crustacean (amphipod)... even a stinging-celled form of life... Keep checking on it, its growth, apparent feeding... and enjoying it, till experience changes your mind otherwise. Bob Fenner>

Re: Unknown Creature in my Live Rock
Thanks you very much for your swift response - with further study of this creature we have determined what it was and just thought that I would write to let you know the outcome of our findings - May I thank WetWebMedia.com
website for the useful information that I found. The unknown creature that we found yesterday living in our live rock was no other than a MANTIS SHRIMP. We managed to get it out of the rock and we returned it to the fish store in which the rock was purchased. One of the gentlemen there has a mangrove tank and has taken it home to care for it. Many thanks for your help. Sincerely, Hayley Weighill 
<Ah, good news all the way around. Congratulations on your hunting prowess. Bob Fenner>

Salt mystery
Bob - Thanks for your reply to my 'mini mantis/brown hair/ hermit homicide' note. Good news ... I think I may have 3 or 4 of the original 5 hermits [instead of the 2 the that I reported]. The way they trade shells its hard to tell who's who. I'll take your advice though and attempt to find the "mystery predator" of hermit #1 before adding more livestock. The first LFS question I get is "do you hear clicking at night?" the answer is "no" [so far]. Would a mantis large enough to 'take down' my blue legged hermit always signal its presence with a 'clicking noise'?
<Ah good, and no to absolutely hearing (or even seeing) Mantis Shrimp (stomatopods)>
Regarding topping off. My system is at 1.0215 SG and my target is 1.023. I know that freshwater top off is the recommended practice. However, I've been adding prepared 1.023 water and checking daily for an SG increase. Two weeks and about 2 gals of this practice hasn't moved the SG up.
<Takes a long time with the stated practice... just top off with straight freshwater... this will even take a while>
There's also been a 5gal [system 37gal w/ 50#LR] 1.023 water change during this time. My understanding is that salt doesn't evaporate and therefore its concentration increases as evaporation occurs. Does it matter if the SG sample is taken from the top or bottom of the water column [the system has active filtration/skimmer/power head
currents] ... Is there an aspect of start up tank biochemistry countering my attempts to raise SG?
<Hmm, well this is actually a matter of density, not really salinity... And you are adding other dissolved solids in the way of foods, supplements... You understand there is more at work here... Read over the salinity piece on the www.wetwebmedia.com site please... And do keep making partial water changes... best way of assuring homeostasis>
As always ... thanks in advance for your insight! Tom Stecik, Dallas
<A pleasure. Bob Fenner>

What's that clicking sound?
Every night when my lights turn off I can hear a faint clicking sound coming from the tank. The tank has 72 pounds of Manono live rock that was cured 3 months ago. There are numerous snails and red legged and left handed crabs. I have a Percula clown, yellow tailed damsel, purple tang and a flame angel. Occasionally I find a dead crab floating on the bottom of the tank. My fear is that the clicking noise is a mantis shrimp and the occasional dead crab was its dinner. I was wondering if you have any insights as to what this noise could be and if it is a mantis shrimp, what should I do before it kills a fish. Note: I never hear the clicking sound when the lights are on and I start to hear it immediately after the lights turn off. Thank you. Rob
<<Hmm, could be a Mantis (order Stomatopoda), an Alpheid Shrimp (Pistol), or one of many other possibilities. Generally a Mantis would smash, pulverize the remains... even if it were a small specimen, so I don't think it is one in this case.
If it were me, I'd either put out a meaty bait (in the front corner of your tank) at night in the end of a tall, narrow glass, like an olive jar) or go ahead and rent or buy a "live mouse trap" from the local fish store, or the Home Depot/Lowe's, and bait it the same... and see what comes out at night. Bob Fenner >>

Mantis Trap
Hey Bob, 
I received my shipment of rock last week from flexures and had somewhat of a shock on my system. My corals refused to open for several days the fish stayed at the surface of the water. Now everything seems to be doing fine, except for an unwanted visitor that came with the rock.
I am pretty sure that it is a mantis shrimp, although I can't find any pictures of one. It is about 1 and 1/2 or 2 inches long, brownish in color, rather flat, and extremely fast. It keeps its pinchers curled up next to it's body. Do you think it is a mantis? 
<Sounds like one to me... apt description>
Do the traps on the market work?
<Usually, yes>
What would you use for bait?
<Anything meaty... and discrete... big enough and solid enough>
And I can already see all of my crabs climbing in the thing. Do you have any suggestions?
<Put the crabs back, toss the Mantis... look it up on the net, under the name Stomatopod>
Sorry to bother you, but one other thing. I now have 80 lbs of live rock. I want to get rid of my wet/dry. I have ordered some Eheim Ehfimech and plan on placing it in the 40 gallon sump. I want to also use some carbon, just not sure on how to set it all up?
<Place the anaerobic media on the bottom of the sump, the carbon in a reusable Dacron bag there on top...>
Always Appreciative,  Diane
<And always "here"... right now with my Diana in the Maldives. Bob Fenner>

Plan for removing Mantis
We are pretty much convinced that this crab we saw out in plain view before we started draining the tank could not have been our emerald crab. How big do emerald crabs usually get? This guy is about 4 -5 in long when he's looking you in the eye! Our little 1 - 1 1/2 in guy couldn't have grown that much in 3 weeks could he? 
<No... this is likely "the butler who did it"... Pull it... boil five minutes per pound in salted water...>
Now we suspect that this much larger crab ate our emerald crab and is the attacker that we had thought to be a mantis.....hmmm....well, when we were draining the tank he crawled into a hole and we took the rock out on a garbage bag to try to coax him out of it....no luck , after a 1/2 hour we set the rock back in the tank overnight hoping he'd crawl out looking for water....but no such luck on that route either. This is probably how he got into the tank in the first place. Hiding and refusing to come out. He could have been the one "spitting out rocks" and making tunnels couldn't he (when we thought it was a mantis shrimp)? 
<Yes to all, get rid of this provocateur!>
We need a good strategy for getting him out in case the fresh water bath doesn't work...I am worried that the new rock could be harboring similar creatures that may be stubborn....should we just try to stab him in there and pull him out "on the stick"? (Last resort of course.) Any suggestions? Thanks! :) RT >>
<Whatever it takes... the freshwater dip will likely work... the animal will weaken, walk out, fall out on its own... Congratulations. Bob Fenner>

Still trying to catch Mantis
Hello! I took out the mysterious red rock as you suggested. Thanks. I don't want to cause any more problems! I am wondering now if it is a bad idea to put any forms of rubber into the tank...we bought a rubber check valve to create a new trap for the mantis...still haven't caught the sucker...and I thought I had better check before using it. Thanks! :) RT
<<The temporary use of such material is probably not a problem... no sign of this animal? I'm starting to wonder if a rock by rock removal and search and destroy mission is recommendable? Bob Fenner>>

Mantis help
Hello again! I wrote to you concerning a mantis shrimp the other day and I am concerned that perhaps I am on the wrong track....Let me tell you our symptoms again... Last week we lost 3 green Chromis, a lawnmower blenny, and a cleaner shrimp. There are nowhere to be found. I have a 92 gal. aquarium with 45 lbs of live rock that has been set up for just over a year. I spoke to an employee of FFExpress who alerted me to the fact that I may have a mantis shrimp on my hands who has just recently grown large enough to do some real damage. We hear "popping" noises sometimes at night in the tank, but from what I have read, mantis shrimp either don't make any noise and "slice and dice" or are the noise makers and "club" their prey to death with repeated blows. Generally what we hear are isolated "pops" or two to three at a time. (which doesn't sound characteristic). We know that there is something living in the live rock because long before I bought my 100 gal clean up crew there was something in the rock "spitting" out pieces of rock and making holes in it. the "spit out pieces" look almost like pumice...with many small holes in them and usually a whitish color...that are about the size of a nickel...usually blocking a hole of some kind. I have had cases of "missing fish" before (usually Chromis), but figured that they had been sick and found a hole to crawl into to die out of sight. We have been trying to make our own traps for this never before seen creature but are not having much luck. It is very distressing. I thought that maybe we just had a pistol shrimp because the popping noises were so few in number...but would they be capable of so many deaths? 
<Would have to be several Pistol (Alpheid) Shrimp to do this much damage... do think "it" is likely a growing Mantis (Stomatopod) Shrimp>
Maybe we have a mantis and a pistol...??? 
<Possibly, but the former would likely eat the latter...>
maybe I am stressing over nothing??? 
<No, or we're both stressing over nothing>
Needless to say I would very much like to replace the fish that we have lost but I am afraid to do so if it means more sacrifices.....we look in a lot (especially lately) at night to see if we can catch the nocturnal nightmares but haven't seen anything!!!! There is a cave style formation in the tank and we fear that that is the reason we never see it...can come out in there without really "coming out" into view for us. We have never found a molting that belonged to anyone other than our cleaner shrimp...another problem in our detective work...as far as trying to figure out what the creature is...I don't know what to do. Any more clues? If it is a pistol shrimp, I've read they are much more harmless....are they trapped in the same fashion (which hasn't been working)? 
<Yes, by baiting, trapping, and they are much more harmless... it's not "them">
Any suggestions you may have are welcome as the LFS here has no clue what to do when it comes to saltwater and most of our advice and research is done on the net. Thanks! RT
<Yes, do condition this critter onto eating something other than your livestock... something meaty in a tank corner placed right before lights out... and do buy, install a "live mouse trap" (it's the same as a "mantis shrimp trap") from your warehouse home improvement store (Lowe's, Home Depot...) if your LFS doesn't sell, rent them... Put in the same food (if you're lucky, quick, quiet, you'll see the Mantis coming out to feed on the bait items... don't scream!)...
You'll soon be rid of this pest. Then you can re-stock your fishes. Bob Fenner>

Re: help
Big Problem!!!! Ugh! This can be so frustrating!!! :( I tried what you said below last night and took a large chunk of fresh shrimp and dropped it into the tank but before it could touch the "ground" my "mammoth" clarkii clownfish (about 5 in.) swooped over and grabbed it like a hungry shark and swam off with it!!!! It went to a remote corner of the tank and was shaking it and munching like it hadn't eaten in weeks (although that is definitely not the case!)!!! This was all after lights out and I was very aggravated.
I half hoped the mantis would come out and do battle! Isn't that awful? What kind of monster am I turning into? I read somewhere that you can wrap the bait in a stocking and it will get "stuck" to it momentarily...but I am still concerned that my stupid clownfish will run off with it to a corner of the tank that I won't be able to reach in an attempt to catch the mantis (if it falls for the bait)...ugh! What do you suggest??? 
<Maybe tying, rubber-banding the food item to a plastic rod, rigid airline tubing piece?>
I am afraid that the live bait trap will work he same way...my cleaner shrimp was dying to get into the trap that we made with a mayonnaise jar with a hole in the lid...luckily we made the hole smaller than he could manage. 
<The Mantis Shrimp (actually Stomatopod...) will likely be larger...>
This is all so complicated. My husband is ready to give up. I am a bit more tenacious.
PS. I am still having a great deal of trouble with blue green carpet algae all over my substrate.... advice? 
<Please read over the Algae, and Algae Control materials I have stored at the URL: www.wetwebmedia.com for a good grounding in what can be done to outdo these Cyanobacteria (BGA)>
I am still (it has been 2 months now) doing weekly water changes of 15% and 10% alternating...each time scrubbing rocks with a toothbrush and trying desperately to suck it all out...but it is all back within days...the annoying carpet stuff only started in the last few weeks and has been much more difficult to remove...it sticks itself to the substrate and won't come up in the siphon because the clumps are too heavy and large...we tried "shoveling" a lot of it out small rocks included...but can never get it all and it just comes back within 2 days....very annoying. Water tests are ok...pH = 8.2 (when we use buffer to maintain - necessary often), nitrite = 0, nitrate = almost 0 (probably due to our constant water changes)
<more likely used up by the BGA>
and ammonia = .25 almost regularly...probably due to all of the dying algae after we scrape...which just feeds the new algae that comes to take its place...such a vicious cycle! Yikes!!!! Any help you can offer in both of these areas is greatly appreciated! I am sorry to bug you so often but you are truly an invaluable resource!!! RT >>
<No problem... why I'm here... we should "step back" and think about your system en toto... need to configure your filtration, lighting... to favor other "higher" forms of photosynthetic life... Bob Fenner>

Re: help
One more quick question: How do we keep the other shrimp and crabs etc. away from the bait and eventually live mouse trap? When we try the jar (which it hasn't fallen for) the other critters are constantly trying to get into it. We made the hole small enough that they couldn't ...but open bait? I don't know how well that will go over. Help!!! With so much live rock it would be very difficult to remove the entire clean up crew and the cleaner shrimp from the tank. :( RT
<Yes to the open bait... if it is big enough (a whole cube of frozen/defrosted prepared food, a silverside, big piece of krill... the "other critters" won't eat it all... In fact, the "big dog" will be out... eating, displacing them... Just place it in a open corner
and be ready with flashlight and net...Bob Fenner>

Missing Fish
Hello again! I called FFExpress because I have been having a problem lately with "missing fish". I recently "lost" 4 green Chromis, my lawnmower blenny, and a large cleaner shrimp! All within a week. They are definitely "gone"...and not a trace has been found of them (as often happens when a fish dies :( ) . When speaking with the employee he suggested that I may have a mantis shrimp. I am very concerned! I read on the Internet that they are very difficult to remove and I do not want to lose the rest of my fish! In fact I would like to order more to replace the missing ones but I am now afraid to do so! Water parameters are all under control although we still have some trouble with blue/green algae. I hate to order the Halimeda I was telling you I plan to get to help out with the problem if I am just going to have to dismantle looking for this shrimp! I never really had problems before. Occasionally we'd "lose" Chromis out of nowhere...but now a shrimp and 5 fish in a week!? With no sign of disease? I also recently purchased a 100 gal cleanup crew and who knows how many of those critters may have been lost to this possible mantis shrimp?! 
<These stomatopods (Mantis Shrimp) can be very bad news... but not too hard to get rid of... Try placing some bit of meaty food in the front corner of your tank near "lights out" time... and be ready with flashlight and net...>
The employee said to listen for snapping sounds when the lights are off. I had heard some before (I think) but not all the time or regularly...would that be the sound of it "cracking shells" of snails or crabs? 
<Possibly... or just the Shrimp's arms working...>
It sounded kind of like the noise large fluorescent lights make sometimes, sort of a popping? We didn't know what it was, but it would happen at night when the tank lights were out and only once or twice (the pop) and then it would stop. The live rock has been in my tank over a year now. I cured it right in the tank. Please advise me on how to find out if this critter is what I am dealing with for sure and what to do if it is. The employee suggested a trap...but I am concerned about how to use it properly with out trapping my other fish and shrimp and crabs etc. 
<Do the trap bit... you can get one from a pet-fish source or the same piece of gear from the Home Depot... sorts of stores ("Live mouse trap")>
I would love to do a high salinity "dip" of all the rocks which was his other suggestion...but I don't think it's possible without really disturbing my poor fish, who have been through so much already with all of our blue/green algae cleanup routines over the last two months! Please help! I am very concerned. :( RT
<No to the hypersaline dip... these don't work... And do the meaty bait and/or trap trick... no worries. Bob Fenner>

Mantis Shrimp
Bob,
Been a while since I've written you. Guess all that early advice paid off and things have been going very well with my tanks. My question relates to my 50 gallon reef. There is a Mantis Shrimp in there, I know where he lives, I know what he's eaten so far. There are no more fish in the tank at all, only snails and hermits and I think he's eating them
now too.
I have an XTerminator Mantis Trap, tried and I think at the time there was 1 fish left in the tank (Potter's Angel) so the Mantis ignored the trap or the bait was not to his liking. At this point, there have not been any fish for over a month, do you think I should try the trap again? What type of bait should I use in it? Or, do you have any
"magical" methods of catching these things? The last thing I want to do is tear the rockwork down, of course the rock in question is at the bottom and I think he's got a back door as well. What do you suggest? Thanks, Dave
<How big is that Mantis Shrimp? You should try baiting it out, maybe even netting it once it comes out (early night with bait). Most anything meaty that will hold together should work. A bit of krill, shrimp, scallop, fish... If need be get a clean can and liner out and systematically pull the rock out and remove that Mantis. Bob Fenner>

Warning
I just had an extremely frustrating experience that you may want to share with your readers. I was very, very careful with my new live rock to make sure I did not introduce any mantis shrimp; however, I have learned (the hard way) that they can find their way into your tank through other means. I bought "Bisma worm rock" and a moon stone coral as part of a large order from FFexpress and both turned out to have
mantis shrimp living in them! It took over two months for me to catch them after they got loose in my reef tank and they killed four neon gobies, two citron gobies, three Catalina gobies, two large cleaner shrimp, an anemone shrimp, a small dwarf angel, a Rainford's goby and a Firefish. I can not even begin to tell you how much the experience sucked.
Please warn people to check EVERYTHING they put in their tanks for these evil, vile creatures.
< I thank you (and can assure you numerous other people will do so) for your timely and necessary message: Yes, everything collected from the wild is capable of bringing in a myriad of life with it... I have even seen fishes (!) shipped in on otherwise dry-appearing live rock... 
Sorry to read of your losses, and thank you once again for relating your experiences.
Bob Fenner>

Mantis Shrimp
I caught a mantis shrimp in my live rock and pulled it out of the tank. I could not bear to kill it and put it in my QT tank instead. Has anyone had success in keeping one? Is it too dangerous? Should I kill it? Are they really that bad?
< Success? Yes! These crustaceans can be fabulous captives. Many are gorgeous and very interesting (though shy and retiring) behaviorally... It's just that they can also be quite destructive: eating fish and non-fish livestock in a typical set-up. If you have the inclination, by all means, keep the species of Mantis you have... and study up on it. Some stay small...Bob Fenner>