I've got a Bradley and I keep the brine simple.
1/4 cup of pickling salt
1-1/2 - 2 cups Demarara brown sugar
about a table spoon of Mrs. Dash
about a table spoon of garlic powder.
1/2 teaspoon or red pepper flakes and a teaspoon of black pepper.
4 litres of water that's gone trough a Brita filter - don't use Abbotsford water from the tap - it has too much flavour.
I cut my fillets from three average (sockeye size) fish into two inch cross sectional pieces - this fills my four trays just right.
I brine the fish in the fridge for 48 hours. I find this to work a lot better than 24 hrs. since I've cut back the salt in the brine. I find that I get a better, to my taste, rubbery texture finished product.
After decades of smoking experiments - I now only use alder chips/pucks. I use 6 pucks for a full smoke of fish.
I take the fish out of the brine and give it a quick cold water rinse. I don't scrub the fish with my hand any more with the lower salt content brine. I spray my trays with PAM edible mold release, and arrange my fish onto the trays right after the rinse. I'll place all the thickest pieces on the bottom tray and arrange the thinnest, tail sections, on the top tray.
Once arranged on the trays, I'll dab dry the fillets with paper towel then give them a sprinkle of freshly cracked pepper from my grinder. I like the pepper flavour from the course grind.
After 1-1/2 - 2 hours of air dry on the counter, I transfer them into my pre-heated smoker. I really watch my temperature and make sure I never heat it over 150 degrees F. throughout the whole event. Otherwise you cook the fish. I used to keep the top vent closed thinking it would really infuse the smoke but that's not what you want to do. I now keep the vent 3/4 open to let the moisture laden heat out of the smoker - after all, you are trying to dehydrate the fish while infusing smoke into the flesh.
3-6 hours later depending on the outdoor humidity and outdoor temp. my product is ready. As soon as the fish has the same resistance as your palm has when you lightly press it with your finger - its done.
I now just pull the power cord and open the door letting it cool to ambient temp. then I zip lock bag it and put in in the fridge. I can't resist a piece right away but its always best after at least two days of refrigeration in the zip lock.
That's the way I like it.