I use foil on the wood box and on the bottom of the smoker. Sure makes clean up easier.
I don't do much fish but a few weeks ago I did a 29 inch steelhead (big trout). Had to cut it in half to fit in the 009. It came out very good using the spicy chicken rub. I cleaned the smoker as usual and left the door open. A week later it still had a strong fish smell. I finally put a chunk of wood in it and let it smoke for about 4 hours. Smell gone!