Help Please.

please help me identify this thing. it's really fast. it was attached to my goldfish's tail

http/tinypic.com/r/1zqty4n/7

Help. i isolated it. and it looks weird.

Can't say I've seen anything like that before, but a site that might be able help Id it is called What Bug is That? http/www.whatsthat...er-bugs/page/3/, if you post your picture there they might be able to tell you all about it.

Just had a look at the site myself and what you have caught off your gold fishes tail is a fish louse. Best kill it and keep a look out for any more.

Looks like Argulus I think.

Go here Fishdoc.co.uk