I want to make a vivarium out of a 10gal. The water level will only come up to 33-50% of the tank height (12"), so I'm wondering if a Fluval 1+ filter is safe to use. I looked at the directions, but there is nothing about danger of submersing the cord underwater. There is just some vague picture of the filter underwater and I am concerned about if there is a limit on how much the electric cord can be submerged. (dont want to electrocute myself or the animals)