that's another advantage of putting the base inside the faces, you cut one long split for the tank depth and dock it to length for the base and ends, makes accuracy a lot easier.
cheapest/easiest way to deal with glass is to buy "splits" off a wholesaler. they are basically long rips off a full sheet, the width of which should be one of the dimensions you need, so you are only cutting in one axis for most of your parts.
hope that makes sense?
if you are going to be cutting a lot of glass, get yourself a speed cutter like this one: (hope pic works)
