Hitch Hiker ID Please

[97tahoe]

I have noticed this little guy a few times after lights out under the moon lights and tonight I caught him with my turkey baster.
I have a few bristle worms and im pretty sure thats not what it is, its not a worm.
When hes running around on the rocks his tail is like curled up under him. When hes setting still he kinda flatens out. He is about 1/4 inch with his tail tucked under him and about a 1/2 inch streched out.
What is it?
Is it bad?
I have only ever seen this one or at least one a time if there are more than one.
Here it is curled up

 

[97tahoe]

and one streched out

 

[97tahoe]

maybe a little better, not sure

 

[jb rekit]

Looks like a big pod.
Something will probably eat him soon

 

[viet-tin]

yea jus an amphipod. there harmless n a good source of food 4 ur fish.

 

[nm reef]

I agree...some sort of copepod/amphipod/isopod...for the most part harmless and beneficial. There are a very few that can pose problems but they are rare.

 

[bang guy]

Gammarus Amphipod.

 

[97tahoe]

Thanks for the replys.
I put him(her)back in the tank

 

[footbag]

I have a million of them in my fuge. Cool little guys! From what I've observed they eat deitrus.