"White wine with fish" gets you about halfway.

It's true that you want acidity, and true that most fish dishes are happier with a white. But there's a world of difference between a plate of oysters and a piece of grilled tuna. The first wants something bracing and mineral, Muscadet or Chablis. The second is meaty enough to take a chilled red without blinking.

Work from the weight of the dish rather than the colour of the flesh, and factor in the sauce, which usually matters more than the fish itself.