Is this a cirolanid isopod?

[tubsy3]

Hi all,

I found a small isopod in my tank when i fist got my live rock. The lfs told me that it was an algea eater isopod. Today I caught an even bigger one that looks like a cirlolanid. Sorry for the blurry pics. He was in a cup with a tiny pistol shrip i also got out of the rocks. Caught him latched onto the shrimp twice. Put it under light and it didnt let go. Poked it a bit and it finally let go. Should I not add fish? I still have a peppermint shrimp, snails, hermits, and a zebra gobi in the tank as they were the cleanup crew/hitchhiker on my live rock.

http://i141.photobucket.com/albums/r41/tubsy3/IMG_0767.jpg
http://i141.photobucket.com/albums/r41/tubsy3/IMG_0768.jpg
http://i141.photobucket.com/albums/r41/tubsy3/IMG_0769.jpg


I tried poking and prodding but he wouldnt get into a full ball. Man i really hope its not the bad isopod. If it is what should i do? Just add no fish for a few months? Is it ok to have the shrimp and gobi/snail/hermits in there or are they jsut providing food?

[dhnguyen]

Yep sure looks like it to me.

http://www.reefkeeping.com/issues/2006-02/bp/index.php

[BrianPlankis]

That does look like a Cirolanid Isopod, but the pictures are pretty blurry. But the fact that you couldn't get it to roll into a ball is not a good sign, that pretty much eliminates the "algae eating" isopod (Sphaeromatids).

I would try doing the stinky water trap I recommend in my article to see if you can capture any more of them:

http://www.reefkeeping.com/issues/2006-02/bp/index.php

Waiting 6 months might be an option, but with the zebra goby in the tank they have a food source. Taking the zebra goby out and waiting 6 months would be a better bet. The pistol shrimp, snails, etc are most likely not a food source and I wouldn't worry about those.

You asked in your PM if anemones would be safe, they would be, but remember anemones should not be put into new tanks, a minimum of 6-12 months is recommended before they are added. A great thread on why is found here:

http://forum.marinedepot.com/Topic23945-9-1.aspx

Brian

[tubsy3]

update

I took him out and played some more with it. It turned into a ball! But only got it to do it once. It likes to jsut sit there looking dead and wont respond. Still a little worried. When it was curled up from the side it looks like a circle so I am hoping its a good guy now.....I am not sure that it looks like a perfect sphere or anything but from the side it looked circle to me.

[Paintbug]

thats a Cirolanid. the big eyes are a give away. its a small one as well. this will give you a side by side pic of a Cirolanid and Sphaeromatid isopods.

http://www.reefkeeping.com/issues/2002-05/rs/index.php

[affableamerican]

Agree on the big eyes. I'm not sure that Sphaermatid isopods roll up into tight balls (like amphipods). Here's a pic of Sphaermatids in my tank:

http://reefcentral.com/gallery/data/500/1314570666_isopod.jpg

[Randall_James]

The isopods are directly related to the "potato bugs" on terra firma so yea, the do roll up just like them.

I was told any isopod with black eyes is not a good thing