Shane, I immediately love you, man
I don't know what Lexan is, but would've loved being named "Lexan" because it sounds like a name that other dudes would say, "Dumb name" but inside would think "That's an untouched chick magnet, 'you've got my freak'n attention' name that if I wasn't balled-and-chained a matter of a few years before all of these "bumbles" and single sites, I'd probably still be an amateur male gigalo :P. (not being facetious... half joking, half serious).
Definitely will look into that. Wondering if thick styrofoam would work too (on all sides but front & top). Also had a random idea after I posted this... maybe insulate all sides & bottom and then use scrap wood (whether pallet wood and/or left over untreated wood) to make it an little indoor 55 gallon "pond" (using wood to dress up exterior). However, have it raised by approx 20" to 24" off floor with wood boards dressing it up from rim to the floor, have a hinged access for small, hidden sump & plumbing, hanging light/lights from ceiling, the perfect huge piece of driftwood that extends way up & out the tank near the ceiling to help conceal power plug(s) that plug into outlets on my ceiling (yet, during winter I'd have a lid of 3 glass pieces with snug fitting cutout around wood), and then make a skinny bar ledge on at least one side for pulling up a barstool, talking with friends, cocktail, watching football, yet have a darn high table bar with integrated discus pond (pond serving as grow out and or possible spawning tank at times). I'd position it so to divide
the space between my left bay and right bay closest to the doors side of the garage.
Remind me to upload pics of garage... might help with visual.