Yeah but you still have a cold water tank against a tank that needs a constant temperature. There would be some fluctuation every time it was flushed even with a heater. The acrylic (I really hope it's not glass) layers would only protect so much. I do think they are pretty to look at but I find them very impractical. I like to build computers and I would consider using them to make the oil cooled aquarium towers but never to put fish in.
I agree with Mekko though if I had the money to spend on a tank like that I would use it to make a drip system for more Bettas. You know what makes Bettas better? More Bettas!