A burning cold-blooded shounen adventure. Takes all the usual tropes and puts them in a nature story about salmon. The art makes for great jokes, where the fish alternate between cartoonish-anthropomorphised and realistic depictions of fish. When you see it you'll know what I mean.
Story feels a little dry, characters don't have much depth (maybe those are related). It's good though. Has kind of a Gurren Lagann spirit.