Public aquarium tenders rarely ask for a price first. They ask three questions: what is the thickest block you can cast, how do you bond it, and which built tank can we visit. A supplier who cannot answer all three is a sheet trader.
Four capabilities that decide the bid
What a large viewing panel actually looks like
A marine hall window of 3,000 mm × 4,000 mm with 4 m of water head behind it typically lands at 100–120 mm cast acrylic, not the 25 mm a buyer might expect from a glass comparison. At that thickness the edge is no longer a simple cut: it is machined to a taper, bonded into a steel or concrete rebate, and sealed on a gasket that allows the panel to move.
Weight is the second surprise. At 120 mm the panel for that window weighs about 1.75 tonnes, so the frame, the lifting plan and the access route become part of the panel specification, not an afterthought.
The bond line is the failure point
Most tank leaks we are asked to diagnose are not panel failures. They are bond-line failures, usually from solvent cement used on a thick joint, which leaves a porous line that fails after a few hundred fill-and-drain cycles. The correct route for thick panels is a polymerised bond with a controlled cure, followed by a pressure test before the tank is handed over.
How the frame rebate is detailed is covered in acrylic aquarium window frame detail, and the capability side in public aquarium acrylic panel supplier.
Frequently Asked Questions
Q: How thick are large aquarium viewing panels?
A:For a window around 3,000 × 4,000 mm with 4 m of water head, cast acrylic lands at roughly 100–120 mm. Thickness scales with water depth and viewing span, so a buyer comparing against glass will usually underestimate by a factor of five.
Q: What is the main cause of acrylic aquarium leaks?
A:Bond-line failure, usually from solvent cement on a thick joint. Panels over 50 mm need a polymerised bond with controlled cure and a pressure test before handover; the acrylic itself is rarely the weak point.
For aquarium panel drawings with water depth, viewing span and frame detail, email oversales@rpplexiglass.com and we will return a thickness and bond schedule.