It will stick unless you have a load of oil, etc. I would count on needing to hold the pan above the coals to control the heat. An Open Country pot grabber is $4 at REI and 1.2oz. Wish for an UL spatula while you are at it.
I experimented with a bunch of really light (read thin) aluminum cake pans for UL fry pans and they basically sucked. The non-stick ones were all too heavy. That is why I wished for a wok.
If you get out of the fish-in-one-piece frame of mind, you can cook it better in a small lid-type pan when cut into smaller pieces. Fantastic when sauteed with good stuff like shallots, onions, garlic, mushrooms, etc. Do it somewhere other than camp-- your big furry buddies will smell it for miles :) A little white wine, a wild rice mix, and some freeze dried veggies. YES!