The Billingsgate Seafood Market knows how to fry a fish. I don't say this lightly; there's a lot that needs to go right in order to produce something more than the oily, thick-battered fare you're likely to find in most Calgary pubs. Their fish is fresh (the place is primarily a fish market - one of the few in the city) , their cut is ample, their batter is thin, tasty, and just a little bit crunchy. A coating of house-made tartar sauce on each flaky piece seals the deal. The accompanying fries are fine, but are typically not made to order (unlike the fish), so they can vary from fryer-fresh to a limp, luke-warm.
There's more to the menu than fried fish but I was disappointed with their bland fish tacos and their cheese-rich-but-fish-poor tuna melt. The seafood chowder is hearty and better than most at this price-level, but the quality can vary. They clearly know their fried fish, however, and I've never been disappointed with either their cod or halibut offerings. If you're in the area and craving a proper fish fry, give this place a try.