Key word here is "destroying"...that's what will eventually happen to your internal components like servos, electronics, etc. Even though "fog juice" smokers don't leave an oily film, the "fog" will condense on components inside the tank. The smoke juice is water and various polyols (sticky, syrupy...think corn syrup or pancake syrup). Eventually, the condensation will cause corrosion and build up a sticky film. This isn't a big problem on tank exterior surfaces because the fog isn't closed in and condensing on the surfaces very much before it blows away. And any surface deposits can be simply wiped away with a moist rag or Q-tip.
If you want damage smoke, it would be best to add tubes leading to and discharging thru smoke ports without letting smoke leak inside the tank.