Sea trout flyfishing in the Norwegian fjords is a lot of fun, and everybody shold try it.
As long as they use their brain and follow some simple rules. The minimum legal "killing-size" is 35 centimeters, but I recommend that people (if they must kill the fish) kill those between 500 - 1000 grams. The bigger fish shold be fished C&R since it's that fish that has the genes we flyfishermen want to go on.
Now, I'm no expert when it comes to flyfishing for seatrout, but during the years I have learned somethings. both from the flyfishing my self and other people.
The most all-around rod for seatrout flyfishing is a fast action 7 wt. This kind of rod will make it easy to cast bigger flies in the wind. And trust me, there will be more days with wind, then without wind. A 5 wt rod is nice for the times you are using thin, long tippets and small flies.The most all-around flyline is a intermediate line, but you can use sinktips and floating lines too. Although I feel that the floating lines can make it hard to feel "connected" to the fly.
The reel MUST be made from materials that can stand the saltwater, and the same goes for the brake. There's nothing that will ruin your gear as fast as saltwater! And the reel shold have the capacity to take minimum 100 meters of 20 lbs backing. You may never need it, but one day maybe you will. Just like me :D
I'm not shure if there is something wrong with the sea trout in Trondheim area, but I have nerver caught a sea trout on a pure baitfish imitation. The closest thing is a zonker. These are the ones I use most of the time.
Now, what the seatrout really likes are shrimp imitations, nearly all the seatrout I catch, take on a shrimp.
The orange shades are the most popular. When you are retriving the fly, you will have to imitate the movement of the bait you are trying to imitate. But sometimes doing the opposite thing can trigger the fish to take. And another very imortant ting is that you don't need flies of many different colours, but rather different sizes.
Well this picture tells it all.
The best time for sea trout in Trondheim is April - May and August - September. And I usually fish a few hours before and after low tide.
That's about all, get out and try it!