There are several threads (and dozens of posts) that contain discussions about the "perfect fish." Since you're registered for the forums, it's very easy for you to do a search for them. Just go to the search page, type the word perfect in the keyword field, change the date range to 1 year and click the Submit button. Voila, they're all there for you to see.

There was a fairly long discussion in the last few days, so here's a link to that thread to get you started. It contains detailed information, so you might want to just skim over it, if you're trying to avoid spoilers.