Do shrimp eat crabs

Question
QUESTION: Hi,

I bought about 40lbs of live rocks but not all at one time, but from the same company. After a month I notice something that looks like a shrimp and a nice size. I also notice about six crabs that was very fast. I actually watch the shrimp ( shrimp looked like he has 50 legs) catch the crab and hold him for a minute or so and run under a live rock. Will the shrimp eat everything in the tank. I have 2 damsels, bi-color blenny, 15 hermit crabs and 2 snails. I was also told that I would have some bristle worms but never saw any.

ANSWER: Hey Regna, (is that the right spelling?)

Please search for MANTIS shrimp

look at the images/pictures of mantis shrimp and see if is like any of those that you find...

If you have one, then i am sorry... But, you will have to get rid of him...

You can setup a 'species' tank for him or bring him to your lfs...

They are predatory and will kill and eat crabs, shrimp, fish, snails, and everything it can.

ALSO, do not touch him or grab him...  depending on the type of mantis, they will cut you BAD, or or break a small bone...

some species can break glass.. They can create a 'clicking noise'.  like snap, mostly at night...  They are actually creating a shock wave and 'stunning' thier prey.  Sometimes that shockwave creates a spark / flash under the water...

But, like i said, they will devestate your tank...

Bristle worms arent a problem.. they are a bit ugly, and you dont want to touch them, but they will eat any left over food and dead critters, ... SO, to control thier growth and population, feed your fish less, and remove any dead things quickly...


PLEASE let me know if MANTIS SHRIMP is what you got in your tank???

You can post pictures of that guy on my new forum at www.thelittleocean.com

WE would love to see it..


BTW:  you should talk to the place you gt the rock from and tell them THANKS

---------- FOLLOW-UP ----------


Squilla Shrimp   QUESTION: This is the Shrimp that I told you about

Answer
Hello Regna

That is definately a MANTIS shrimp.. And although they are pretty cool to look at they are going to devastate your tank... the next thing to go will be the bi-color blenny, cause as you know that fish sleeps in little holes which are going to be a trap when the mantis corners it...

You will lose all your snails and crabs and anything that crawls or is slow...

It is best to trap him, (or kill him), to get rid of him...

If he hides in a rock, you might be best to pull that rock out and either put it into another 'species only tank', where he can be by himself, and only eat what you put in there for him to eat, or to freeze him or 'dry the rock' to get him...

the 'humane' method for euthansia would be freezing, but not sure if you can get the rock into the freezer??? or if you want the rock in your freezer  :)

maybe call your supplier that you got the rock from and ask him what you should do with the mantis...

But, until he is gone, you will continue to watch your good critters become lunch...

sorry, but best wishes...

please log onto my new forum at www.thelittleocean.com and share your experience with this guy... i have told several members there about you and your shrimp and they are anxious to see and hear about it...

so, i hope to see you there...

good luck


bill