Do Mantis Shrimp Traps Work? I think I may need one...

[buzz]

I went home last night and started staring at my tank to find it again. Nothing so far...perhaps if I can trap it safely, I can make the ID, and let it go about it's business if it's something harmless.
I don't want to wait until it is a nuisance before I act on it. That's why I asked for help in the first place. By my saying that I have some time before it hits about 2 inches, all I meant was that I have some time to work on getting the ID. I definitely don't want to wait until my critters start disappearing...

 

[john f]

The most common mantis hitchhickers are smasher type mantis.
These usually get no bigger than 3 inches in length. They do not kill fish but do like to eat small snails and crabs.
I have at least one of these in my large reef tank. I really don't worry too much about him as my fish are safe ( I have even small green chromis that have been in there for months ) and any snails he eats can be replaced over time.
These small smasher mantis will also take frozen foods like formula one or mysis shrimp. So if you feed your tank often they might not even kill the snails for food.
Another point is these small smashers only live for a short while. The species I have tops out at 3" before it dies at about 4 years of age. Since mine is already very close to 3" I doubt he will live much longer than 1-2 more years.
So if after my tank has been up and running for a year I need to add a few more turbo snails, big deal.
This is far less stressful on me than trying to hunt him down every night.
Now if you have a large spearer type mantis (like a peacock mantis) he WILL kill fish and needs to be removed ASAP.
This type of mantis almost never arrive as a hitchhicker on pacific rock, and NEVER comes in on Florida rock.
John

 

[beefman]

If u Hear like a loud Clicking type of noise is that a sign that u have one????

 

[kpogue]

I just did some reading on this 2day. Most mantis do not click when they are beating the H out of a fish. They may though when they are killing a snail or a crab. Then it is a rapid click. If you hear one or two clicks at a time the article said it was most likley a pistol shrimp. I know I have pistols because I found a few "babies" in my sponge last night.

 

[beefman]

Well i hear Clicking nosies throughout the night alot but mostly in a 2 clicking way but sometimes 3-4. i have tried and look for the all the time but still no chance.So hopefully my guys are ok. i have found 1 snail dead but that was from a while but still when i got all this live rock.

 

[fshhub]

kpogue, find his den then remove it (that rock) form teh tank, and then use the club soda, in a bucket or something else

 

[kpogue]

Thanks - I'll give it a shot. Just as long as it's not near the bottom. At 2 feet deep and 170 lbs of rock - it could be a little tough!

 

[buzz]

If it's even in the rock....if what I have is a mantis, it left the rock and is burrowing in the sand somewhere....

 

[broomer5]

The mantis shrimp in my tank has been in there for a year or two. I don't know for sure how long - added live rock over a long period of time.
I've tried the trap - nothing but hermits.
I've done the plastic soda bottle - nothing but hermits.
I pulled half of the live rock in my tank out, including the rock that it lives in ( bottom of the stack ) did the high salinity rock dips - still nothing - it must have been out in the tank that day.
Go figure
Weeks will go by without a sound or sighting - then the click click click.
My wife spotted it 3 nights ago - up at the top of the tank's rockwork, tapping away at my inner overflow box.
Almost netted the little s.o.b. - but alas - it's very fast and extremely shy when we're nearby.
I gotta get this little sucka outta there !
Can't keep emerald crabs for very long - and I have some velonia

 

[yammer]

When I was first setting up my tank and added live sand (from Fiji), it came with 3 Mole Crabs. These are small white crabs varying in size from about 6 to 12mm. The key is that they live in the sand and burrow VERY rapidly through it whenever startled. As I mentioned, they are small and white but have two arms and legs that they use to move about. I would often find them with just the tip of their head and two legs extended out of the sand (I believe they are filter feeders). Perhaps this is what you have?
One other factor is that they don't survive in aquariums very long. Mine were gone after the first month. You can find a good reference for them in the "Modern Reef Aquarium" series (vol 3) by Nilsen and Fossa.
You said that your glimpse looked somewhat like the pictures in previous posts, but this is just another option to consider. If you do happen to have Mole crabs, they are harmless and unfortunately short lived.