Do I even need a balloon?

http://lifterproject.online.fr/orville/index.htm

This guy built an ionic lifter from balsawood and tin foil that was able to levitate a small, padded enclosure with a mouse inside. This would have to be scaled up considerably to support the basics that a small hamster needs to be comfortable for any length of time (water will be the real challenge due to weight) but if upon doing the math the size turns out to be reasonable, this might be a way to avoid having to deal with large balloons and pressurized helium altogether. A thin wire would send power up to the lifter and also serve as the mooring line. This may turn out to be more expense and hassle than it's worth but the way I see it, if I wanted to fly this more than once, doing it this way would spare me the steep recurring cost of new helium.