The Georgia Aquarium's acrylic panels range from 2 inches to 2 feet thick, depending on the tank and the pressure the water exerts on it

The Georgia Aquarium in Atlanta does not use traditional glass for most of its major exhibits. Instead, the facility uses acrylic — a clear plastic material that is stronger than glass and can be cast in much larger sheets without the weight penalty. The thickness varies dramatically across the building because deeper tanks and larger viewing areas need thicker material to withstand the force of the water pressing against them.

The most famous example is the Ocean Voyager exhibit, which holds 6.3 million gallons of water and contains the facility's whale sharks. The acrylic panels in that tank are among the thickest in the building, reaching up to 2 feet (24 inches) in some sections. By contrast, smaller tanks and shallower exhibits use panels as thin as 2 inches. The difference comes down to physics: water pressure increases with depth, so a panel 50 feet down needs far more material to resist the force than a panel 10 feet down.

Key Takeaways

  • The Georgia Aquarium uses acrylic panels rather than glass, which allows for larger viewing areas and greater strength at lighter weight.
  • Panel thickness ranges from 2 inches in shallow or small tanks to 2 feet in the deepest exhibits like the Ocean Voyager.
  • Water pressure determines thickness — deeper tanks require thicker acrylic to prevent cracking or failure.
  • Acrylic can be cast in single sheets large enough to create unobstructed views of entire exhibits, something glass cannot achieve at this scale.

Why acrylic instead of glass

Glass is brittle and heavy. A single pane of glass thick enough to hold back millions of gallons of water would weigh thousands of pounds and would be nearly impossible to install or replace. Acrylic is flexible enough to absorb stress without shattering, and it is significantly lighter. For a facility the size of the Georgia Aquarium, the weight savings alone make acrylic the only practical choice.

Acrylic also allows the aquarium to create seamless viewing panels. The Ocean Voyager's main window is a single acrylic sheet measuring 203 feet long, 78 feet tall, and 2 feet thick at its thickest point. No glass window of that size could be manufactured or installed. The material's optical clarity is nearly identical to glass — visitors see the exhibits without distortion.

How water pressure determines thickness

Water pressure increases by about 0.445 pounds per square inch for every foot of depth. At 50 feet down, the pressure is roughly 22 pounds per square inch. At 200 feet, it exceeds 87 pounds per square inch. The acrylic panel must be thick enough that the material itself does not flex or fail under that load.

Engineers calculate the required thickness by considering three factors: the depth of the tank, the width of the panel (wider panels experience more total force), and the material properties of acrylic itself. A 2-inch panel works fine for a shallow touch tank where visitors can reach in. A 24-inch panel is necessary for the deepest sections of the Ocean Voyager, where whale sharks swim and the pressure is extreme.

The Ocean Voyager's record-breaking panels

The Ocean Voyager exhibit is the largest in the aquarium and holds the most impressive acrylic installation. The main viewing panel is 203 feet long, 78 feet tall, and weighs 600,000 pounds. It is made of acrylic that reaches 2 feet thick in the deepest sections and tapers to thinner material in shallower areas of the same tank.

This single panel took years to engineer and manufacture. It was cast in one piece to avoid seams that could leak or fail. The panel is so large that it required custom equipment to transport and install. When it was completed, it set records for the largest acrylic panel ever made for an aquarium.

Maintenance and replacement of acrylic panels

Acrylic can scratch and cloud over time, especially in high-traffic areas where visitors touch the surface. The Georgia Aquarium maintains its panels by cleaning them regularly and polishing them to restore clarity. Small scratches do not affect the structural integrity of the material, but they can reduce visibility.

If a panel becomes too damaged or cloudy to use, replacement is a major undertaking. The aquarium must drain the tank, remove the old panel, and install a new one — a process that can take weeks and requires the animals in that exhibit to be moved temporarily. Because of this cost and disruption, the facility prioritizes preventive maintenance and protective barriers in areas where visitors congregate.

Other materials used in the aquarium

While acrylic dominates the major exhibits, the Georgia Aquarium uses other materials in different areas. Some smaller tanks use traditional glass panels, which are adequate for shallow exhibits. Fiberglass is used in some structural elements and tank walls where visibility is not the primary concern. The choice of material always depends on the specific needs of that exhibit.

The building itself uses standard architectural glass in windows and skylights, which is separate from the acrylic used in the animal tanks. Visitors sometimes confuse the two, but the acrylic in the tanks is purpose-built for aquatic pressure and clarity in ways that architectural glass is not.

Frequently Asked Questions

Can the acrylic panels crack or break?

Acrylic is much more resistant to cracking than glass, but it can fail if the thickness is insufficient for the water pressure or if the material is damaged by impact. The Georgia Aquarium designs its panels with safety margins well above the minimum required thickness, so failure is extremely unlikely under normal conditions.

Why does the acrylic sometimes look cloudy?

Acrylic can become cloudy from scratches, algae buildup, or mineral deposits in the water. The aquarium cleans and polishes panels regularly to maintain clarity. Cloudiness does not indicate structural weakness — it is a surface condition that affects visibility but not safety.

How long do acrylic panels last?

Acrylic can last 20 to 30 years or longer if properly maintained, though panels in high-traffic areas may need replacement sooner due to scratching and wear. The Georgia Aquarium replaces panels as needed, with major installations like the Ocean Voyager panel designed to last decades.

Is acrylic stronger than glass?

Acrylic is more impact-resistant and flexible than glass, making it less likely to shatter. However, glass is harder and more scratch-resistant. For aquarium use, acrylic's strength and ability to be cast in large sheets make it the superior choice despite its tendency to scratch more easily.

Can visitors touch the acrylic panels?

Visitors can touch the acrylic, but the aquarium discourages it to prevent scratches and fingerprints. Some exhibits have barriers or signs asking visitors not to touch. The acrylic is durable enough to withstand casual contact, but repeated touching in the same spot can eventually cause visible wear.