Hello, I am trying to design a way to move a platform that is inside a container without any direct connection to the platform. I hope to have a linear guide outside of the container with an electromagnet attached. When the electromagnet is energized it will couple with the platform inside the container with its magnetic field and as the electromagnet moves up and down the platform inside moves as well. The gap between the electromagnet and platform will be between 3-6mm. The platform will weigh less than 2lb. The container will be filled with water. I need the platform to be well attached to the magnet, there can be no drift or slip. The platform will move very slowly. Is this possible? Would a set of permanent magnets work better? Ive read that the lifting type electromagnets dont have much reach. What sort of design would work best? Thanks for any help you guys can give me, I know very little about magnets.