A 125-gallon aquarium is 72 inches long, 18 inches wide and 21 inches tall. Glass aquariums of this size weigh approximately 206 pounds before being filled and 1,400 pounds filled. Acrylic aquariums weigh less.
Glass aquariums are usually preferred over acrylic aquariums because they are less expensive and more scratch-resistant, although scratches can be polished out of acrylic. They also don't yellow over time. Acrylic aquariums have several advantages, such as being more crack-resistant and lighter. Aquariums vary in size, ranging from less than 1/2 gallon to millions of gallons. The largest aquarium in the world is the 12.87 million gallon aquarium in China's Ocean Kingdom as of 2014.