A Shrimp Thing in my Tank

[allanh]

I need help figuring out what is loose in my tank please. I have a fairly new Reef tank. I noticed tonight after the lights were off in the back corner of the tank a group of 3 or 4 translucient shrimp looking things. They were only about a 1/16th to an 1/8 of an inch in length but VERY fast when I tried to net one. They dont seem to venture far from the rock in that corner. As they only like the night, I cant get a picture to post. Any ideas would be helpfull.

I am concerned because also this evening I found one of my hermet crabs dead and without his shell, I FEAR I have a colony of mantis shrimp growing in my tank.

Thank you

[Nano_Steve]

fear not fellow reefer......it doesnt sound like mantis shrimp rather copepods!!! which are very beneficial to your reef ecosystem. they reproduce rather quickly and are great food for smaller fish and faster moving inverts that are able to catch them....trust me, when i saw my first copepod i flipped out and thought of the worst for my tank but quickly realized the benefits they have for the aforementioned ecosystem.

happy reefing, steve

[beareef19]

agree copepod a good tank set up will have many. As for the hermit crab it sounds like it has shed. Hermits will do this as they grow, they come out of their hard shells and molt they, shed the exoskeleton and then return to the hard shell. At this time they are vulnerable because they are very soft.

[Sherri]

When lights out....my tank is crawling with copepods...and my pair of green mandarins are fat & sassy cause of it. It's a good thing!

BTW allanh....Welcome to MAAST!

Sherri

[allanh]

Thank you all for the suggestions. I will relax and enjoy and leave my crtitters be. I had always understood copepods to be smaller, but now that you mention it. My Mandarin hangs out in that corner of the tank also.

[ChrisL]

Are Pods able to swim through the water? Because I have some sort of "pod looking" organism in my tank. The other day while moving a rock, it darted out, but it was so fast and little it was hard to follow where it went. I do have other pods, that are really small, but it doesn't seem like they are able to swim, they get caught in the currents all the time and don't seem as if they can fight it, just settle where the current takes them.

[Yves Nobleza]

do they swim?....could be mysid shrimp too

[Goofball310]

I have to agree with Joshua. From the discription of their size, it sounds more like amphipods or mysid.

[MikeP]

Sounds more like a mysid to me. Look at the excellent hitchhiker FAQ on Reefs.org to see if you can narrow it down. Also Dr. Shimek has some good information on his forum on reefcentral and on his webpage.

-MP