ID: Mantis Shrimp?

I'm setting up a new 28g nano cube, only three weeks old. Was changing the overflow filter tonight and noticed this brown spec on it. Thought it was a large pod at first but after I got it in a glass, I'm almost positive its a baby mantis shrimp. Can anyone ID this for sure?

Also, what experience have you guys had with leaving a mantis in your reef tank? I've never had one, and always read horror stories about them eating fish. Anyone have some input on that as well? I wouldn't mind keeping him if yo think he wouldn't be a problem down the road.

Thanks for your input!

 

Not a mantis shrimp. Looks like an amphipod and it is beneficial to your tank. You'll have a bun of them eventually.

But to be sure...how big is it, really? Or rather, how small is it?

 

Ok, had me worried for a sec, I've got a bunch of copepods and tiger pods already, just hadn't really seen any amphipods this size before. He is .25"

 

Isopod, very bad.

 

OK, they are amphipods....crustaceans, which is why they have a similar body structure to that of the abdomen of a mantis shrimp.

 

Amphipod.

amphipod - Google Search

 

Isopods aren't particularly bad, either.

 

They are nasty if they are attached to your fish.

Reefs.org: Where Reefkeeping Begins on the Internet - Cirolanid Isopods

And another great link a member posted today.

Xtalreef

 

Grrreeaattt, and I already put him back in the tank.

 

Looks like a cirolanid isopod to me. Some are scavengers and some are blood suckers.

Pills, Parasites, and Predators; Isopods in the Reef Aquarium by Ronald L. Shimek, Ph.D. - Reefkeeping.com