What's This - Underwater Tick?

[cconemanband]

I am still trying to get my tank readings correct so I can get my first fish, but in the mean time I was looking in the tank and saw this creature that is rather white/tannish with long antennas crawling on the back glass. Sure looks just like a big tick or kind of like a beetle but flatter. Anybody know what this is and is it going to hurt any fish I would put it in the tank. When I started the tank, the only thing I put in it was 3 pieces of live rock. I did not scrape the rocks, but just put them in.

Thanks.....Steve!

 

[dralarms]

Need a picture to be sure.

 

[quarryshark]

Maybe a Nudibranch?
A pic would help.

 

[mle421]

sounds like a pod to me. they're very beneficial if it is.