Some of the links on this forum allow SMF, at no cost to you, to earn a small commission when you click through and make a purchase. Let me know if you have any questions about this.
I never brine fish. I'll marinate in a non acidic marinade though. If you use a acidic marinade keep it short or the acid will start to "cook" the fish.
I'm with FlaGriller (Jim) on this one. I never brine fish. Not even cheaper fish like catfish (although I VERY rarely eat them). Why not just enjoy the tasty Trout?
FWIW, to change things up, go to a local Spanish/Mexican grocery store and pick up some fresh/frozen Banana leaves - and wrap the fillet in one. Apply tasteful spices/marinade and seal the leaf and leave on grill for a little while. VERY good.