Transparent aluminum

Transparent aluminum is a transparent material that was much stronger and lighter than plexiglass. While plexiglass sheets for a 60x10 tank with 18,000 cubic feet of water would need to be six inches thick, a transparent aluminum sheet would only need to be one inch thick.

In 1986, a time traveling Montgomery Scott gave the formula to Dr. Marcus Nichols in exchange for plexiglass to enclose a tank on board the HMS Bounty in order to transport the humpback whales George and Gracie to the 23rd century. Nichols was eventually recognized as the inventor of transparent aluminum. (Star Trek IV: The Voyage Home).