We think it was September last year that the episode of "Tanked" to which you're referring first aired on Animal Planet. We didn't see it, but you can catch some of the construction phase, plus the "reveal," on YouTube.
The tank, which apparently dispensed real gumballs, was more than 250 gallons, carried 50 fish of assorted varieties, and was more than 8 feet tall. As it was outside on the verandah, a custom cooling mechanism was incorporated into the design in an attempt to keep the fish at a healthy temperature, but from what we gleaned from some aquatic forums we visited, it didn't work properly, all the fish apparently died within four days, and the tank had to be dismantled.
We gather, from discussions we read within the aquarium community online, that the two guys (brothers-in-law) who own the Las Vegas-based Acrylic Tank Manufacturing business upon which the show is based, have earned a somewhat dubious reputation for building these elaborate, gimmicky tanks that look pretty but aren't actually viable living spaces for the fish they are meant to house. Fish enthusiasts were upset by a tank built to double as a skateboard ramp, for example, fearing that its dual purpose would traumatize the occupants.
Another accusation leveled at the show's stars is that they do not acclimate the fish to their new environment, nor cycle the water through repeatedly as you're meant to when a new tank is being established, as evinced by the superclean sand and water when the final "reveals" are done, and a lack of algae that would be the norm in a new tank environment.
A tank built in the style and to the exact dimensions of a phone booth, commissioned for a private residence in Las Vegas, also proved to have inherent problems. It's currently for sale on eBay, but is being stored at a business in North Las Vegas called Blue Reef Aquatics. A very helpful staff member we spoke with there confirmed our suspicions that the piece has issues, describing it as "temperamental." The vertical orientation would require significant and costly modification to the filtration system to get enough oxygen into the water to support saltwater fish, we were told, so it's currently home to some goldfish. (With a $5,000 price tag, that's got to make it one of the most expensive goldfish bowls in the world.) Apparently, the previous owners, who relocated back to New York, had the filter running through a hole in their garage wall and the necessary water-cooling in the Las Vegas heat was adding $300-$400 per month to their electric bill. Ouch.
As to the tank built for what was then the Mob Experience, now Mob Attraction, at the Tropicana, this simpler specimen was created for the first show in the "Tanked" series and survived the remodel and rebranding of the exhibit, so you can still see it today by the entrance, complete with glowing, bubble-emitting sticks of dynamite, and submerged flat-screen TVs showing old gangster movies. The more conventional tank at Silverton, also created by ATM, has also stood the test of time to remain one of the city's cooler and more popular free attractions.
For more about the numerous aquariums around town, both free-to-view and paid exhibits, see QoD 7/10/09 in the Archives.
