Re: 4 Foot Vivarium Build From The Ground Up
With all the effort you're putting into this, I would recommend two things. Either add a float valve in the trough area (hidden is fine) so you don't have to worry about evap causing your canister to suck air. Or the other option would be to sump the filter. With a stand being that size, you could easily fit a 10 gallon tank underneath and make your own wet/dry filter which would be chump to maintain and you can hide an ATO valve in the sump.
I can look up the place, but there was a glass shop in Rockville that I used to deal with back in the day. They were affordable and could cut whatever size glass you need at reasonable rates. They also would bevel the edges if asked for little to no charge if you asked. For sliding doors that would be ideal to reduce chipping and friction.