He whined that I had done it "wrong"

stating facts is not whinning , bryan.
you were wrong so I said you were wrong.

Doesn't work that way - material thrown within the ship will encounter resistance with the air, hull, etc. This will generate a force equal to the force of the propellant, thus neutralizing the thrust of the propellant. Its the ol' opposite and equal reaction thingie - the movement of the propellant will "push" on the ship, but the interaction of the propellant with the ship will push back equally. Net effect - zero thrust.

your still wrong.

the magnitude of the force produced by the tank is irrelevant. What is relevant is the momentum produced will remain zero so long as that tank stays in a sealed pipe.
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.