Glass is usually held together with silicone. If it has a rim, and you plan to keep it you’ll have to be careful in the removal. I’ve never done so myself. As for the glass itself I have read that using fishing line to separate the panes works really well and very easily.
I was thinking that the factory frames top and bottom would be hard to remove without breaking them. So my idea was to, carefully cut the frames away with a Dremel, and then dismantling the glass. To rebuild, 2 front to back glass braces and Euro bracing around the top.
Got it apart. as stated, held together with silicone. Tank is in basement and no basement door. Have to carry up the steps. Thought it would be easier to take apart. Glass is still heavy though.