For anyone living in the sticks north of Munich (or anyone with a craving for Steckerlfisch) this place
http://www.satzfischzucht.com/kontakt.htm
is doing its annual 'Fischerfest', there's beer, there's music and there's extremely yummy Steckerlfisch (trout, not mackerel) and other 'fishy' food.
Plus, you can have a peek at the fish ponds.