MATERIALS · AQUARIUMS

Aquarium Glass Types: Float, Low-Iron & Tempered Glass Explained

Standard glass, low-iron glass and tempered panels are not interchangeable terms. Here is what each means before you buy, drill or commission a custom tank.

Updated September 23, 2026 · By the AquariumSetup team

“Glass aquarium” hides several material choices. Most standard tanks use ordinary float glass. Premium display tanks may use low-iron glass for clearer edges. Some manufacturers temper specific panels, which matters enormously if you ever plan to drill the aquarium.

The common aquarium glass types

GlassWhy it is usedMain tradeoff
Standard float glassAffordable, widely available, scratch resistantGreen edge/tint becomes more visible as thickness rises
Low-iron glassClearer, less green tintHigher cost
Tempered glassUsed in some panels/designs for strength characteristicsCannot be drilled; failure mode is sudden fragmentation
Laminated / specialtyCustom engineering use casesNot typical mass-market DIY material

Standard float glass

This is the default material in many rectangular aquariums. It is inexpensive, hard to scratch during normal cleaning and easy to manufacture in standard sizes. The familiar green tint is most visible when you look through a thick edge.

Low-iron glass

Low-iron glass reduces the green cast and is attractive for rimless aquascapes and display tanks where color rendition matters. It is an aesthetic upgrade, not a reason to ignore panel thickness, bracing or stand support.

Tempered panels and drilling

Do not guess

If you plan to drill an aquarium, confirm the exact panel construction first. Attempting to drill tempered glass can destroy the panel instantly. A sticker on one panel does not automatically describe every other panel in the tank.

The site already has a tank-drilling guide; use that only after the panel material is confirmed.

Glass thickness is an engineering choice

Panel thickness depends on tank length, height, bracing, rim design and allowable deflection. Do not copy a thickness from another aquarium simply because the gallon volume looks similar. A tall narrow tank and a shallow breeder tank create different stresses.

Glass vs acrylic is a separate decision

If your real question is material rather than glass subtype, read the site's existing glass vs acrylic aquarium comparison. Glass generally wins on scratch resistance and standard sizing; acrylic becomes more attractive for very large or custom-shaped displays.

Frequently asked questions

What type of glass is used for aquariums?

Standard mass-market aquariums commonly use float glass, while premium display tanks may use low-iron glass for clearer viewing. Tempered glass may be used on certain panels, but construction varies by manufacturer and model.

Can you drill tempered aquarium glass?

No. Tempered glass can shatter when drilled. Never drill an aquarium panel unless you have confirmed from the manufacturer or reliable documentation that the specific panel is non-tempered and suitable for drilling.

Is low-iron glass stronger than regular aquarium glass?

Low-iron describes optical composition, not a blanket safety upgrade. Aquarium panel thickness and construction must be engineered for the tank dimensions regardless of clarity.

Next step

New to fishkeeping? Start with our complete beginner aquarium setup guide. Choosing filtration? Use the filter hub to compare options by tank size.