I have the same smoker as Mike's. My dad was a butcher and we used to smoke fish in a brick smoker with a real fire in a side fire box. Apple wood was always the preferred wood....Prune the apple trees and use that.
I am a believer in using a meat thermometer. I dry overnight in the refigerator. I used to lay paper towels over the fish while it dried overnight. Alot of times the paper would stick to the fish. So wax paper is fine under and on top. I cure for 4 hours with a dry cure that liquifies. I smoked a batch for many hours at low heat and got basically lox...great tasting but very soft. It is the salt that keeps it from molding but I still used twice as much brown sugar as salt. I am told that after an hour in this smoker the fish has absorbed all the smoke it will so it is really not necessary to use more than one bucket of chips..this smoker has a high capacity for chips...I use the new Luhr Jensen chunks which work well...In the old brick smoker with the fire box we went to Sawduct Supply and bought gunny sacks of alder and put that on the coals...nothing finer...A charcoal fire with alder chips is great too. The propane smoker allows for a set it and forget it smoke job...I babysat my first batch but the next one will be set at 160 degrees and the process should be done after 3 hours of so. Best bet is to experiment.