I haven't tried it yet, myself, but I've read of people propping 10 gallons up on their side to get a taller enclosure out of the same tank. You might have to build your own lid, or modify the current one as the original top would no longer be efficient, and I'd be careful of heavy decorations, as the frame isn't constructed to support weight on its side, but it could work if you don't have a taller tank handy at the moment.