Nanos are bad enough to manage due to the small size. No sense at all in adding to the woes with poor gas exchange with a low surface area to volume ratio. It may fit the "spot" you chose, and you may "prefer" tall tanks, but it is not a really great idea. For stability and overall health of the system, marine tanks should be wider than they are tall. This advice is as old as the hobby itself is. Tall narrow tanks are fresh water tanks, where dissolved oxygen saturation levels are higher.
That said, the tank you want to build needs 10mm glass, on the low side, with 12mm being preferable. 9mm is to thin.