That looks really cool! Although i cant imagine how much it cost for the glass :/ keep in mind that because of the critical angle of viewing when you look into the tank sides will appear as mirrors which could be a weird sensation when in the bathroom LOL. And also im assuming youre putting that huge and beautifully made ornament as a center piece? because it would be weird considering that youre in the bathroom and the other side is a kitchen :P
And as for advice. umm so at homedepot you can buy DIY like closet sliding door mounts. like they are basically rails that go under or above closet doors so that you can slide the,. you might wanna consider constructing a system that is similar to a claw drop toy machine so that you can move and slide the lights around :P
http://www.cheesebikini.com/cam/art/m5agqenq(q11m).jpg
like that claw thing on top but with lights :P
only thing missing is a bubble under the aquarium for your very lucky kids to stick their heads in and observe the fish
Its a wonderful project and im looking forward to see it completed!