That subject line is the punch line to the joke, "What do you call a fish with with no eyes?"
Ad Blankestijn (still embarassingly unsure how to pronounce that name) has started a Fish O’ Japan Almanac beginning with aji. Really interesting stuff, and HOLY SHIT am I excited to eat some anko (Blackmouth Angler) this winter. I had no idea those things were edible. The only thing he could do better would be to provide the kanji, although to be honest you don’t have to write the kanji when you order at a sushi restaurant, and often fish names are written in katakana because fish kanji are so obscure, so if you want to bone up on your fish vocab, head over to Japan Navigator.