It's not really the tank you have to waterproof, it's the electronics. The brushed motors in these tanks can run underwater with no problem, but motherboards are a little more sensitive. Depending on the tank and how much space you have inside I've seen guys use small Tupperware containers, putting all the electronics in and sealing the container and having one hole for the wires to go in and out that is sealed up with silicone. I've never done one myself, but if I did I think I would stick to the less expensive Electronics, as opposed to something like an El mod or an ibu. Burning up a $50 board is one thing, burning up a $200 board makes you feel a lot worse.